diff --git a/examples/on-the-fly/kbv-condition-diagnosis/generate.ts b/examples/on-the-fly/kbv-condition-diagnosis/generate.ts
index 25652d78..e82c4115 100644
--- a/examples/on-the-fly/kbv-condition-diagnosis/generate.ts
+++ b/examples/on-the-fly/kbv-condition-diagnosis/generate.ts
@@ -25,9 +25,6 @@ if (require.main === module) {
             treeShake: {
                 "kbv.basis": {
                     "https://fhir.kbv.de/StructureDefinition/KBV_PR_Base_Condition_Diagnosis": {},
-                    // Referenced as a Condition.subject target; included so the
-                    // reference type resolves to the profile's base resource.
-                    "https://fhir.kbv.de/StructureDefinition/KBV_PR_Base_Patient": {},
                 },
             },
         })
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_blood_pressure_profile.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_blood_pressure_profile.py
index 4f810582..6ee1c5ea 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_blood_pressure_profile.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_blood_pressure_profile.py
@@ -397,7 +397,7 @@ def validate(self) -> dict[str, list[str]]:
         errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8480-6"}]}}, "systolic", 1, 1))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8462-4"}]}}, "diastolic", 1, 1))
-        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","USCoreCareTeam","USCoreOrganizationProfile","Patient","USCorePractitionerProfile","USCoreRelatedPersonProfile"]))
+        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]))
         warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
         warnings.extend(validate_enum(self._resource, profile_name, "code", ["2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"]))
         warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_body_weight_profile.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_body_weight_profile.py
index f67d63dc..00254658 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_body_weight_profile.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_body_weight_profile.py
@@ -225,7 +225,7 @@ def validate(self) -> dict[str, list[str]]:
         errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
         errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
         errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","USCoreCareTeam","USCoreOrganizationProfile","Patient","USCorePractitionerProfile","USCoreRelatedPersonProfile"]))
+        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]))
         errors.extend(validate_excluded(self._resource, profile_name, "valueCodeableConcept"))
         errors.extend(validate_excluded(self._resource, profile_name, "valueString"))
         errors.extend(validate_excluded(self._resource, profile_name, "valueBoolean"))
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_vital_signs_profile.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_vital_signs_profile.py
index 7702ff04..bbbbb9e3 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_vital_signs_profile.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_vital_signs_profile.py
@@ -334,7 +334,7 @@ def validate(self) -> dict[str, list[str]]:
         errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
         errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
         errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","USCoreCareTeam","USCoreOrganizationProfile","Patient","USCorePractitionerProfile","USCoreRelatedPersonProfile"]))
+        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]))
         warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
         warnings.extend(validate_enum(self._resource, profile_name, "code", ["2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"]))
         warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
diff --git a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBloodPressureProfile.ts b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBloodPressureProfile.ts
index cf2750a7..00d1bf70 100644
--- a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBloodPressureProfile.ts
+++ b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBloodPressureProfile.ts
@@ -417,7 +417,7 @@ export class USCoreBloodPressureProfile {
                 ...validateSliceFields(res, profileName, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8480-6"}]}}, "systolic", ["valueQuantity"]),
                 ...validateSliceCardinality(res, profileName, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8462-4"}]}}, "diastolic", 1, 1),
                 ...validateSliceFields(res, profileName, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8462-4"}]}}, "diastolic", ["valueQuantity"]),
-                ...validateReference(res, profileName, "performer", ["PractitionerRole","USCoreCareTeam","USCoreOrganizationProfile","Patient","USCorePractitionerProfile","USCoreRelatedPersonProfile"]),
+                ...validateReference(res, profileName, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]),
             ],
             warnings: [
                 ...validateEnum(res, profileName, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]),
diff --git a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBodyWeightProfile.ts b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBodyWeightProfile.ts
index 9b31b34c..781a0f11 100644
--- a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBodyWeightProfile.ts
+++ b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBodyWeightProfile.ts
@@ -332,7 +332,7 @@ export class USCoreBodyWeightProfile {
                 ...validateChoiceProhibited(res, profileName, ["effectiveTiming","effectiveInstant"]),
                 ...validateReference(res, profileName, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]),
                 ...validateReference(res, profileName, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]),
-                ...validateReference(res, profileName, "performer", ["PractitionerRole","USCoreCareTeam","USCoreOrganizationProfile","Patient","USCorePractitionerProfile","USCoreRelatedPersonProfile"]),
+                ...validateReference(res, profileName, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]),
                 ...validateChoiceProhibited(res, profileName, ["valueCodeableConcept","valueString","valueBoolean","valueInteger","valueRange","valueRatio","valueSampledData","valueTime","valueDateTime","valuePeriod"]),
             ],
             warnings: [
diff --git a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreVitalSignsProfile.ts b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreVitalSignsProfile.ts
index 38c052e2..2ce509e3 100644
--- a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreVitalSignsProfile.ts
+++ b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreVitalSignsProfile.ts
@@ -335,7 +335,7 @@ export class USCoreVitalSignsProfile {
                 ...validateChoiceProhibited(res, profileName, ["effectiveTiming","effectiveInstant"]),
                 ...validateReference(res, profileName, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]),
                 ...validateReference(res, profileName, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]),
-                ...validateReference(res, profileName, "performer", ["PractitionerRole","USCoreCareTeam","USCoreOrganizationProfile","Patient","USCorePractitionerProfile","USCoreRelatedPersonProfile"]),
+                ...validateReference(res, profileName, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]),
             ],
             warnings: [
                 ...validateEnum(res, profileName, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]),
diff --git a/src/api/writer-generator/python/profile-validation.ts b/src/api/writer-generator/python/profile-validation.ts
index 9c02b1bc..6e4b8004 100644
--- a/src/api/writer-generator/python/profile-validation.ts
+++ b/src/api/writer-generator/python/profile-validation.ts
@@ -76,9 +76,9 @@ export const collectValidateBody = (
                     `warnings.extend(validate_must_support(self._resource, profile_name, ${JSON.stringify(pyName)}))`,
                 );
             }
-            if (field.reference && field.reference.length > 0) {
+            if (field.reference && field.reference.resource.length > 0) {
                 helpers.add("validate_reference");
-                const allowed = field.reference.map((ref) => resolveRef(ref).name);
+                const allowed = field.reference.resource.map((ref) => resolveRef(ref).name);
                 errorLines.push(
                     `errors.extend(validate_reference(self._resource, profile_name, ${JSON.stringify(pyName)}, ${JSON.stringify(allowed)}))`,
                 );
diff --git a/src/api/writer-generator/typescript/profile-validation.ts b/src/api/writer-generator/typescript/profile-validation.ts
index 1fd48921..0423af78 100644
--- a/src/api/writer-generator/typescript/profile-validation.ts
+++ b/src/api/writer-generator/typescript/profile-validation.ts
@@ -42,9 +42,9 @@ export const collectRegularFieldValidation = (
     if (field.mustSupport && !field.required)
         warnings.push(`...validateMustSupport(res, profileName, ${JSON.stringify(name)})`);
 
-    if (field.reference && field.reference.length > 0)
+    if (field.reference && field.reference.resource.length > 0)
         errors.push(
-            `...validateReference(res, profileName, ${JSON.stringify(name)}, ${JSON.stringify(field.reference.map((ref) => resolveRef(ref).name))})`,
+            `...validateReference(res, profileName, ${JSON.stringify(name)}, ${JSON.stringify(field.reference.resource.map((ref) => resolveRef(ref).name))})`,
         );
 
     if (field.slicing?.slices) {
diff --git a/src/api/writer-generator/typescript/utils.ts b/src/api/writer-generator/typescript/utils.ts
index 7c5420d5..fc9ab91a 100644
--- a/src/api/writer-generator/typescript/utils.ts
+++ b/src/api/writer-generator/typescript/utils.ts
@@ -79,8 +79,8 @@ export const resolveFieldTsType = (
         if (field.type.name === "CodeableConcept") return `CodeableConcept<${tsEnumType(field.enum)}>`;
         return tsEnumType(field.enum);
     }
-    if (field.reference && field.reference.length > 0) {
-        const resolved = field.reference.map((ref) => (resolveRef ? resolveRef(ref) : ref));
+    if (field.reference && field.reference.resource.length > 0) {
+        const resolved = field.reference.resource.map((ref) => (resolveRef ? resolveRef(ref) : ref));
         const references = resolved
             .map((ref) => (isFamilyType?.(ref) ? `string /* ${ref.name} */` : `"${ref.name}"`))
             .join(" | ");
diff --git a/src/typeschema/core/field-builder.ts b/src/typeschema/core/field-builder.ts
index 984e178c..18b9d286 100644
--- a/src/typeschema/core/field-builder.ts
+++ b/src/typeschema/core/field-builder.ts
@@ -7,15 +7,17 @@
 import type { FHIRCoding, FHIRSchemaDiscriminator, FHIRSchemaElement } from "@atomic-ehr/fhirschema";
 import type { Register } from "@root/typeschema/register";
 import type { CodegenLog } from "@root/utils/log";
-import { packageMetaToFhir } from "@typeschema/types";
+import { isProfileIdentifier, packageMetaToFhir } from "@typeschema/types";
 import type {
     BindingIdentifier,
     EnumDefinition,
     Field,
+    FieldReference,
     FieldSlice,
     FieldSlicing,
     Name,
     PackageMeta,
+    ProfileIdentifier,
     RegularField,
     RichFHIRSchema,
     TypeIdentifier,
@@ -90,18 +92,37 @@ function isExcluded(register: Register, fhirSchema: RichFHIRSchema, path: string
     return new Set(requires).has(fieldName);
 }
 
+/** Resolve reference targets into two independent facts: `resource` — the base
+ *  resource types a reference literal may point at (profiles resolve to their
+ *  base specialization, deduped) — and `profiles` — the profile conformance
+ *  expectations, preserved for profile-aware consumers. */
 const buildReferences = (
     register: Register,
     fhirSchema: RichFHIRSchema,
     element: FHIRSchemaElement,
-): TypeIdentifier[] | undefined => {
+): FieldReference | undefined => {
     if (!element.refers) return undefined;
-    return element.refers.map((ref) => {
+    const resource: TypeIdentifier[] = [];
+    const profiles: ProfileIdentifier[] = [];
+    const seen = new Set<string>();
+    for (const ref of element.refers) {
         const curl = register.ensureSpecializationCanonicalUrl(ref as Name);
         const fs = register.resolveFs(fhirSchema.package_meta, curl);
         if (!fs) throw new Error(`Failed to resolve fs for ${curl}`);
-        return mkIdentifier(fs);
-    });
+        const id = mkIdentifier(fs);
+        let resolved: TypeIdentifier = id;
+        if (isProfileIdentifier(id)) {
+            profiles.push(id);
+            const baseFs = register.resolveFsSpecializations(fs.package_meta, fs.url)[0];
+            if (!baseFs) throw new Error(`Failed to resolve base specialization for ${curl}`);
+            resolved = mkIdentifier(baseFs);
+        }
+        if (!seen.has(resolved.url)) {
+            seen.add(resolved.url);
+            resource.push(resolved);
+        }
+    }
+    return { resource, profiles: profiles.length > 0 ? profiles : undefined };
 };
 
 const extractSliceFieldNames = (schema: FHIRSchemaElement): Pick<FieldSlice, "required" | "excluded" | "elements"> => {
diff --git a/src/typeschema/types.ts b/src/typeschema/types.ts
index 81220182..2a163a22 100644
--- a/src/typeschema/types.ts
+++ b/src/typeschema/types.ts
@@ -370,9 +370,14 @@ export type LogicalTypeSchema = { identifier: LogicalIdentifier } & Specializati
 
 export type SpecializationTypeSchema = ResourceTypeSchema | ComplexTypeTypeSchema | LogicalTypeSchema;
 
+export type FieldReference = {
+    resource: TypeIdentifier[];
+    profiles?: ProfileIdentifier[];
+};
+
 export interface RegularField {
     type: TypeIdentifier;
-    reference?: TypeIdentifier[];
+    reference?: FieldReference;
     required?: boolean;
     excluded?: boolean;
     array?: boolean;
@@ -401,7 +406,7 @@ export interface ChoiceFieldInstance {
     required?: boolean;
     excluded?: boolean;
     array?: boolean;
-    reference?: TypeIdentifier[];
+    reference?: FieldReference;
     binding?: BindingIdentifier;
     enum?: EnumDefinition;
     min?: number;
diff --git a/test/api/write-generator/__snapshots__/introspection.test.ts.snap b/test/api/write-generator/__snapshots__/introspection.test.ts.snap
index 36407f54..90ec2fa4 100644
--- a/test/api/write-generator/__snapshots__/introspection.test.ts.snap
+++ b/test/api/write-generator/__snapshots__/introspection.test.ts.snap
@@ -2608,9 +2608,9 @@ exports[`IntrospectionWriter - TypeSchema output Check all introspection data in
 {"identifier":{"kind":"complex-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Narrative","url":"http://hl7.org/fhir/StructureDefinition/Narrative"},"base":{"kind":"complex-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Element","url":"http://hl7.org/fhir/StructureDefinition/Element"},"fields":{"status":{"type":{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"code","url":"http://hl7.org/fhir/StructureDefinition/code"},"required":true,"excluded":false,"array":false,"binding":{"kind":"binding","package":"shared","version":"1.0.0","name":"NarrativeStatus","url":"urn:fhir:binding:NarrativeStatus"},"enum":{"isOpen":false,"values":["generated","extensions","additional","empty"]}},"div":{"type":{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"xhtml","url":"http://hl7.org/fhir/StructureDefinition/xhtml"},"required":true,"excluded":false,"array":false}},"description":"Base StructureDefinition for Narrative Type: A human-readable summary of the resource conveying the essential clinical and business information for the resource.","dependencies":[{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"code","url":"http://hl7.org/fhir/StructureDefinition/code"},{"kind":"complex-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Element","url":"http://hl7.org/fhir/StructureDefinition/Element"},{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"xhtml","url":"http://hl7.org/fhir/StructureDefinition/xhtml"},{"kind":"binding","package":"shared","version":"1.0.0","name":"NarrativeStatus","url":"urn:fhir:binding:NarrativeStatus"}]}
 {"identifier":{"kind":"resource","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Resource","url":"http://hl7.org/fhir/StructureDefinition/Resource"},"fields":{"id":{"type":{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"string","url":"http://hl7.org/fhir/StructureDefinition/string"},"required":false,"excluded":false,"array":false},"meta":{"type":{"kind":"complex-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Meta","url":"http://hl7.org/fhir/StructureDefinition/Meta"},"required":false,"excluded":false,"array":false},"implicitRules":{"type":{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"uri","url":"http://hl7.org/fhir/StructureDefinition/uri"},"required":false,"excluded":false,"array":false},"language":{"type":{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"code","url":"http://hl7.org/fhir/StructureDefinition/code"},"required":false,"excluded":false,"array":false,"binding":{"kind":"binding","package":"shared","version":"1.0.0","name":"Language","url":"urn:fhir:binding:Language"},"enum":{"isOpen":true,"values":["ar","bn","cs","da","de","de-AT","de-CH","de-DE","el","en","en-AU","en-CA","en-GB","en-IN","en-NZ","en-SG","en-US","es","es-AR","es-ES","es-UY","fi","fr","fr-BE","fr-CH","fr-FR","fy","fy-NL","hi","hr","it","it-CH","it-IT","ja","ko","nl","nl-BE","nl-NL","no","no-NO","pa","pl","pt","pt-BR","ru","ru-RU","sr","sr-RS","sv","sv-SE","te","zh","zh-CN","zh-HK","zh-SG","zh-TW"]}}},"description":"This is the base resource type for everything.","dependencies":[{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"code","url":"http://hl7.org/fhir/StructureDefinition/code"},{"kind":"complex-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Meta","url":"http://hl7.org/fhir/StructureDefinition/Meta"},{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"string","url":"http://hl7.org/fhir/StructureDefinition/string"},{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"uri","url":"http://hl7.org/fhir/StructureDefinition/uri"},{"kind":"binding","package":"shared","version":"1.0.0","name":"Language","url":"urn:fhir:binding:Language"}],"typeFamily":{"resources":[{"kind":"resource","package":"hl7.fhir.r4.core","version":"4.0.1","name":"DomainResource","url":"http://hl7.org/fhir/StructureDefinition/DomainResource"},{"kind":"resource","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Bundle","url":"http://hl7.org/fhir/StructureDefinition/Bundle"},{"kind":"resource","package":"hl7.fhir.r4.core","version":"4.0.1","name":"OperationOutcome","url":"http://hl7.org/fhir/StructureDefinition/OperationOutcome"}]}}
 {"identifier":{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"decimal","url":"http://hl7.org/fhir/StructureDefinition/decimal"},"description":"Base StructureDefinition for decimal Type: A rational number with implicit precision","base":{"kind":"complex-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Element","url":"http://hl7.org/fhir/StructureDefinition/Element"},"dependencies":[{"kind":"complex-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Element","url":"http://hl7.org/fhir/StructureDefinition/Element"}]}
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 {"identifier":{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"unsignedInt","url":"http://hl7.org/fhir/StructureDefinition/unsignedInt"},"description":"Base StructureDefinition for unsignedInt type: An integer with a value that is not negative (e.g. >= 0)","base":{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"integer","url":"http://hl7.org/fhir/StructureDefinition/integer"},"dependencies":[{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"integer","url":"http://hl7.org/fhir/StructureDefinition/integer"}]}
 {"identifier":{"kind":"primitive-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"uri","url":"http://hl7.org/fhir/StructureDefinition/uri"},"description":"Base StructureDefinition for uri Type: String of characters used to identify a name or a resource","base":{"kind":"complex-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Element","url":"http://hl7.org/fhir/StructureDefinition/Element"},"dependencies":[{"kind":"complex-type","package":"hl7.fhir.r4.core","version":"4.0.1","name":"Element","url":"http://hl7.org/fhir/StructureDefinition/Element"}]}
 {"identifier":{"kind":"binding","package":"shared","version":"1.0.0","name":"BundleType","url":"urn:fhir:binding:BundleType"},"valueset":{"kind":"value-set","package":"hl7.fhir.r4.core","version":"4.0.1","name":"BundleType","url":"http://hl7.org/fhir/ValueSet/bundle-type"},"strength":"required","enum":{"isOpen":false,"values":["document","message","transaction","transaction-response","batch","batch-response","history","searchset","collection"]},"dependencies":[{"kind":"value-set","package":"hl7.fhir.r4.core","version":"4.0.1","name":"BundleType","url":"http://hl7.org/fhir/ValueSet/bundle-type"}]}
@@ -2911,15 +2911,17 @@ exports[`IntrospectionWriter - flat profile output Check bodyweight flat profile
       },
       "required": true,
       "excluded": false,
-      "reference": [
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "Patient",
-          "url": "http://hl7.org/fhir/StructureDefinition/Patient"
-        }
-      ],
+      "reference": {
+        "resource": [
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "Patient",
+            "url": "http://hl7.org/fhir/StructureDefinition/Patient"
+          }
+        ]
+      },
       "array": false,
       "mustSupport": true
     },
@@ -3015,29 +3017,40 @@ exports[`IntrospectionWriter - flat profile output Check bodyweight flat profile
       },
       "required": false,
       "excluded": false,
-      "reference": [
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "MolecularSequence",
-          "url": "http://hl7.org/fhir/StructureDefinition/MolecularSequence"
-        },
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "QuestionnaireResponse",
-          "url": "http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse"
-        },
-        {
-          "kind": "profile",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "observation-vitalsigns",
-          "url": "http://hl7.org/fhir/StructureDefinition/vitalsigns"
-        }
-      ],
+      "reference": {
+        "resource": [
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "MolecularSequence",
+            "url": "http://hl7.org/fhir/StructureDefinition/MolecularSequence"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "QuestionnaireResponse",
+            "url": "http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "Observation",
+            "url": "http://hl7.org/fhir/StructureDefinition/Observation"
+          }
+        ],
+        "profiles": [
+          {
+            "kind": "profile",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "observation-vitalsigns",
+            "url": "http://hl7.org/fhir/StructureDefinition/vitalsigns"
+          }
+        ]
+      },
       "array": true
     },
     "derivedFrom": {
@@ -3050,50 +3063,61 @@ exports[`IntrospectionWriter - flat profile output Check bodyweight flat profile
       },
       "required": false,
       "excluded": false,
-      "reference": [
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "DocumentReference",
-          "url": "http://hl7.org/fhir/StructureDefinition/DocumentReference"
-        },
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "ImagingStudy",
-          "url": "http://hl7.org/fhir/StructureDefinition/ImagingStudy"
-        },
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "Media",
-          "url": "http://hl7.org/fhir/StructureDefinition/Media"
-        },
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "MolecularSequence",
-          "url": "http://hl7.org/fhir/StructureDefinition/MolecularSequence"
-        },
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "QuestionnaireResponse",
-          "url": "http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse"
-        },
-        {
-          "kind": "profile",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "observation-vitalsigns",
-          "url": "http://hl7.org/fhir/StructureDefinition/vitalsigns"
-        }
-      ],
+      "reference": {
+        "resource": [
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "DocumentReference",
+            "url": "http://hl7.org/fhir/StructureDefinition/DocumentReference"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "ImagingStudy",
+            "url": "http://hl7.org/fhir/StructureDefinition/ImagingStudy"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "Media",
+            "url": "http://hl7.org/fhir/StructureDefinition/Media"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "MolecularSequence",
+            "url": "http://hl7.org/fhir/StructureDefinition/MolecularSequence"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "QuestionnaireResponse",
+            "url": "http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "Observation",
+            "url": "http://hl7.org/fhir/StructureDefinition/Observation"
+          }
+        ],
+        "profiles": [
+          {
+            "kind": "profile",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "observation-vitalsigns",
+            "url": "http://hl7.org/fhir/StructureDefinition/vitalsigns"
+          }
+        ]
+      },
       "array": true
     },
     "component": {
diff --git a/test/api/write-generator/__snapshots__/python.test.ts.snap b/test/api/write-generator/__snapshots__/python.test.ts.snap
index 06665095..895f7062 100644
--- a/test/api/write-generator/__snapshots__/python.test.ts.snap
+++ b/test/api/write-generator/__snapshots__/python.test.ts.snap
@@ -1471,7 +1471,7 @@ class UscoreBloodPressureProfile:
         errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8480-6"}]}}, "systolic", 1, 1))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8462-4"}]}}, "diastolic", 1, 1))
-        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","USCoreCareTeam","USCoreOrganizationProfile","Patient","USCorePractitionerProfile","USCoreRelatedPersonProfile"]))
+        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]))
         warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
         warnings.extend(validate_enum(self._resource, profile_name, "code", ["2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"]))
         warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
@@ -1710,7 +1710,7 @@ class UscoreBodyWeightProfile:
         errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
         errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
         errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","USCoreCareTeam","USCoreOrganizationProfile","Patient","USCorePractitionerProfile","USCoreRelatedPersonProfile"]))
+        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]))
         errors.extend(validate_excluded(self._resource, profile_name, "valueCodeableConcept"))
         errors.extend(validate_excluded(self._resource, profile_name, "valueString"))
         errors.extend(validate_excluded(self._resource, profile_name, "valueBoolean"))
diff --git a/test/api/write-generator/__snapshots__/typescript.test.ts.snap b/test/api/write-generator/__snapshots__/typescript.test.ts.snap
index 8a096614..c6bc1688 100644
--- a/test/api/write-generator/__snapshots__/typescript.test.ts.snap
+++ b/test/api/write-generator/__snapshots__/typescript.test.ts.snap
@@ -1735,7 +1735,7 @@ export class USCoreBloodPressureProfile {
                 ...validateSliceFields(res, profileName, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8480-6"}]}}, "systolic", ["valueQuantity"]),
                 ...validateSliceCardinality(res, profileName, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8462-4"}]}}, "diastolic", 1, 1),
                 ...validateSliceFields(res, profileName, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8462-4"}]}}, "diastolic", ["valueQuantity"]),
-                ...validateReference(res, profileName, "performer", ["PractitionerRole","USCoreCareTeam","USCoreOrganizationProfile","Patient","USCorePractitionerProfile","USCoreRelatedPersonProfile"]),
+                ...validateReference(res, profileName, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]),
             ],
             warnings: [
                 ...validateEnum(res, profileName, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]),
@@ -2087,7 +2087,7 @@ export class USCoreBodyWeightProfile {
                 ...validateChoiceProhibited(res, profileName, ["effectiveTiming","effectiveInstant"]),
                 ...validateReference(res, profileName, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]),
                 ...validateReference(res, profileName, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]),
-                ...validateReference(res, profileName, "performer", ["PractitionerRole","USCoreCareTeam","USCoreOrganizationProfile","Patient","USCorePractitionerProfile","USCoreRelatedPersonProfile"]),
+                ...validateReference(res, profileName, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]),
                 ...validateChoiceProhibited(res, profileName, ["valueCodeableConcept","valueString","valueBoolean","valueInteger","valueRange","valueRatio","valueSampledData","valueTime","valueDateTime","valuePeriod"]),
             ],
             warnings: [
diff --git a/test/unit/typeschema/__snapshots__/snapshot.test.ts.snap b/test/unit/typeschema/__snapshots__/snapshot.test.ts.snap
index c93d0803..dacb08dd 100644
--- a/test/unit/typeschema/__snapshots__/snapshot.test.ts.snap
+++ b/test/unit/typeschema/__snapshots__/snapshot.test.ts.snap
@@ -1109,15 +1109,17 @@ exports[`FHIR Schema to Type Schema (snapshot) Custom resource TutorNotification
         },
         "required": true,
         "excluded": false,
-        "reference": [
-          {
-            "kind": "resource",
-            "package": "mypackage",
-            "version": "0.0.0",
-            "name": "TutorNotificationTemplate",
-            "url": "http://example.com/aidbox-sms-tutor/TutorNotificationTemplate"
-          }
-        ],
+        "reference": {
+          "resource": [
+            {
+              "kind": "resource",
+              "package": "mypackage",
+              "version": "0.0.0",
+              "name": "TutorNotificationTemplate",
+              "url": "http://example.com/aidbox-sms-tutor/TutorNotificationTemplate"
+            }
+          ]
+        },
         "array": false
       },
       "message": {
@@ -1154,15 +1156,17 @@ exports[`FHIR Schema to Type Schema (snapshot) Custom resource TutorNotification
         },
         "required": true,
         "excluded": false,
-        "reference": [
-          {
-            "kind": "resource",
-            "package": "hl7.fhir.r4.core",
-            "version": "4.0.1",
-            "name": "Patient",
-            "url": "http://hl7.org/fhir/StructureDefinition/Patient"
-          }
-        ],
+        "reference": {
+          "resource": [
+            {
+              "kind": "resource",
+              "package": "hl7.fhir.r4.core",
+              "version": "4.0.1",
+              "name": "Patient",
+              "url": "http://hl7.org/fhir/StructureDefinition/Patient"
+            }
+          ]
+        },
         "array": false
       }
     },
diff --git a/test/unit/typeschema/ir/__snapshots__/tree-shake.test.ts.snap b/test/unit/typeschema/ir/__snapshots__/tree-shake.test.ts.snap
index 1dac3820..1240a722 100644
--- a/test/unit/typeschema/ir/__snapshots__/tree-shake.test.ts.snap
+++ b/test/unit/typeschema/ir/__snapshots__/tree-shake.test.ts.snap
@@ -5253,29 +5253,31 @@ exports[`treeShake specific TypeSchema Original Patient 1`] = `
       },
       "required": false,
       "excluded": false,
-      "reference": [
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "Organization",
-          "url": "http://hl7.org/fhir/StructureDefinition/Organization"
-        },
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "Practitioner",
-          "url": "http://hl7.org/fhir/StructureDefinition/Practitioner"
-        },
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "PractitionerRole",
-          "url": "http://hl7.org/fhir/StructureDefinition/PractitionerRole"
-        }
-      ],
+      "reference": {
+        "resource": [
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "Organization",
+            "url": "http://hl7.org/fhir/StructureDefinition/Organization"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "Practitioner",
+            "url": "http://hl7.org/fhir/StructureDefinition/Practitioner"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "PractitionerRole",
+            "url": "http://hl7.org/fhir/StructureDefinition/PractitionerRole"
+          }
+        ]
+      },
       "array": true
     },
     "managingOrganization": {
@@ -5288,15 +5290,17 @@ exports[`treeShake specific TypeSchema Original Patient 1`] = `
       },
       "required": false,
       "excluded": false,
-      "reference": [
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "Organization",
-          "url": "http://hl7.org/fhir/StructureDefinition/Organization"
-        }
-      ],
+      "reference": {
+        "resource": [
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "Organization",
+            "url": "http://hl7.org/fhir/StructureDefinition/Organization"
+          }
+        ]
+      },
       "array": false
     },
     "link": {
@@ -5532,15 +5536,17 @@ exports[`treeShake specific TypeSchema Original Patient 1`] = `
           },
           "required": false,
           "excluded": false,
-          "reference": [
-            {
-              "kind": "resource",
-              "package": "hl7.fhir.r4.core",
-              "version": "4.0.1",
-              "name": "Organization",
-              "url": "http://hl7.org/fhir/StructureDefinition/Organization"
-            }
-          ],
+          "reference": {
+            "resource": [
+              {
+                "kind": "resource",
+                "package": "hl7.fhir.r4.core",
+                "version": "4.0.1",
+                "name": "Organization",
+                "url": "http://hl7.org/fhir/StructureDefinition/Organization"
+              }
+            ]
+          },
           "array": false
         },
         "period": {
@@ -5583,22 +5589,24 @@ exports[`treeShake specific TypeSchema Original Patient 1`] = `
           },
           "required": true,
           "excluded": false,
-          "reference": [
-            {
-              "kind": "resource",
-              "package": "hl7.fhir.r4.core",
-              "version": "4.0.1",
-              "name": "Patient",
-              "url": "http://hl7.org/fhir/StructureDefinition/Patient"
-            },
-            {
-              "kind": "resource",
-              "package": "hl7.fhir.r4.core",
-              "version": "4.0.1",
-              "name": "RelatedPerson",
-              "url": "http://hl7.org/fhir/StructureDefinition/RelatedPerson"
-            }
-          ],
+          "reference": {
+            "resource": [
+              {
+                "kind": "resource",
+                "package": "hl7.fhir.r4.core",
+                "version": "4.0.1",
+                "name": "Patient",
+                "url": "http://hl7.org/fhir/StructureDefinition/Patient"
+              },
+              {
+                "kind": "resource",
+                "package": "hl7.fhir.r4.core",
+                "version": "4.0.1",
+                "name": "RelatedPerson",
+                "url": "http://hl7.org/fhir/StructureDefinition/RelatedPerson"
+              }
+            ]
+          },
           "array": false
         },
         "type": {
@@ -6018,29 +6026,31 @@ exports[`treeShake specific TypeSchema ignoreFields regular field 1`] = `
       },
       "required": false,
       "excluded": false,
-      "reference": [
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "Organization",
-          "url": "http://hl7.org/fhir/StructureDefinition/Organization"
-        },
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "Practitioner",
-          "url": "http://hl7.org/fhir/StructureDefinition/Practitioner"
-        },
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "PractitionerRole",
-          "url": "http://hl7.org/fhir/StructureDefinition/PractitionerRole"
-        }
-      ],
+      "reference": {
+        "resource": [
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "Organization",
+            "url": "http://hl7.org/fhir/StructureDefinition/Organization"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "Practitioner",
+            "url": "http://hl7.org/fhir/StructureDefinition/Practitioner"
+          },
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "PractitionerRole",
+            "url": "http://hl7.org/fhir/StructureDefinition/PractitionerRole"
+          }
+        ]
+      },
       "array": true
     },
     "managingOrganization": {
@@ -6053,15 +6063,17 @@ exports[`treeShake specific TypeSchema ignoreFields regular field 1`] = `
       },
       "required": false,
       "excluded": false,
-      "reference": [
-        {
-          "kind": "resource",
-          "package": "hl7.fhir.r4.core",
-          "version": "4.0.1",
-          "name": "Organization",
-          "url": "http://hl7.org/fhir/StructureDefinition/Organization"
-        }
-      ],
+      "reference": {
+        "resource": [
+          {
+            "kind": "resource",
+            "package": "hl7.fhir.r4.core",
+            "version": "4.0.1",
+            "name": "Organization",
+            "url": "http://hl7.org/fhir/StructureDefinition/Organization"
+          }
+        ]
+      },
       "array": false
     },
     "link": {
@@ -6297,15 +6309,17 @@ exports[`treeShake specific TypeSchema ignoreFields regular field 1`] = `
           },
           "required": false,
           "excluded": false,
-          "reference": [
-            {
-              "kind": "resource",
-              "package": "hl7.fhir.r4.core",
-              "version": "4.0.1",
-              "name": "Organization",
-              "url": "http://hl7.org/fhir/StructureDefinition/Organization"
-            }
-          ],
+          "reference": {
+            "resource": [
+              {
+                "kind": "resource",
+                "package": "hl7.fhir.r4.core",
+                "version": "4.0.1",
+                "name": "Organization",
+                "url": "http://hl7.org/fhir/StructureDefinition/Organization"
+              }
+            ]
+          },
           "array": false
         },
         "period": {
@@ -6348,22 +6362,24 @@ exports[`treeShake specific TypeSchema ignoreFields regular field 1`] = `
           },
           "required": true,
           "excluded": false,
-          "reference": [
-            {
-              "kind": "resource",
-              "package": "hl7.fhir.r4.core",
-              "version": "4.0.1",
-              "name": "Patient",
-              "url": "http://hl7.org/fhir/StructureDefinition/Patient"
-            },
-            {
-              "kind": "resource",
-              "package": "hl7.fhir.r4.core",
-              "version": "4.0.1",
-              "name": "RelatedPerson",
-              "url": "http://hl7.org/fhir/StructureDefinition/RelatedPerson"
-            }
-          ],
+          "reference": {
+            "resource": [
+              {
+                "kind": "resource",
+                "package": "hl7.fhir.r4.core",
+                "version": "4.0.1",
+                "name": "Patient",
+                "url": "http://hl7.org/fhir/StructureDefinition/Patient"
+              },
+              {
+                "kind": "resource",
+                "package": "hl7.fhir.r4.core",
+                "version": "4.0.1",
+                "name": "RelatedPerson",
+                "url": "http://hl7.org/fhir/StructureDefinition/RelatedPerson"
+              }
+            ]
+          },
           "array": false
         },
         "type": {
diff --git a/test/unit/typeschema/transformer/reference.test.ts b/test/unit/typeschema/transformer/reference.test.ts
new file mode 100644
index 00000000..384fa8de
--- /dev/null
+++ b/test/unit/typeschema/transformer/reference.test.ts
@@ -0,0 +1,102 @@
+import { describe, expect, it } from "bun:test";
+import type { ProfileTypeSchema, RegularField } from "@typeschema/types";
+import { mkErrorLogger, mkR4Register, registerFs, registerFsAndMkTs } from "@typeschema-test/utils";
+
+describe("reference target resolution", async () => {
+    const r4 = await mkR4Register();
+    const logger = mkErrorLogger();
+
+    registerFs(r4, {
+        url: "http://example.org/StructureDefinition/TestPatient",
+        name: "TestPatient",
+        base: "http://hl7.org/fhir/StructureDefinition/Patient",
+        derivation: "constraint",
+        kind: "resource",
+    });
+
+    it("profile-only targetProfile yields both the base resource and the profile", async () => {
+        // Base Observation.subject references Patient (among others); the profile
+        // restates it with ONLY a Patient profile as target.
+        const ts = (
+            await registerFsAndMkTs(
+                r4,
+                {
+                    url: "http://example.org/StructureDefinition/TestObservation",
+                    name: "TestObservation",
+                    base: "http://hl7.org/fhir/StructureDefinition/Observation",
+                    derivation: "constraint",
+                    kind: "resource",
+                    elements: {
+                        subject: {
+                            type: "Reference",
+                            refers: ["http://example.org/StructureDefinition/TestPatient"],
+                        },
+                    },
+                },
+                logger,
+            )
+        )[0] as ProfileTypeSchema;
+
+        const subject = ts.fields?.subject as RegularField;
+        expect(subject.reference?.resource.map((ref): string => ref.name)).toEqual(["Patient"]);
+        expect(subject.reference?.resource[0]?.kind).toBe("resource");
+        expect(subject.reference?.profiles?.map((ref): string => ref.name)).toEqual(["TestPatient"]);
+        expect(subject.reference?.profiles?.[0]?.kind).toBe("profile");
+    });
+
+    it("profile alongside its base resource dedupes the resource list", async () => {
+        const ts = (
+            await registerFsAndMkTs(
+                r4,
+                {
+                    url: "http://example.org/StructureDefinition/TestCondition",
+                    name: "TestCondition",
+                    base: "http://hl7.org/fhir/StructureDefinition/Condition",
+                    derivation: "constraint",
+                    kind: "resource",
+                    elements: {
+                        subject: {
+                            type: "Reference",
+                            refers: [
+                                "http://hl7.org/fhir/StructureDefinition/Group",
+                                "http://hl7.org/fhir/StructureDefinition/Patient",
+                                "http://example.org/StructureDefinition/TestPatient",
+                            ],
+                        },
+                    },
+                },
+                logger,
+            )
+        )[0] as ProfileTypeSchema;
+
+        const subject = ts.fields?.subject as RegularField;
+        expect(subject.reference?.resource.map((ref): string => ref.name)).toEqual(["Group", "Patient"]);
+        expect(subject.reference?.profiles?.map((ref): string => ref.name)).toEqual(["TestPatient"]);
+    });
+
+    it("plain resource targets carry no profiles", async () => {
+        const ts = (
+            await registerFsAndMkTs(
+                r4,
+                {
+                    url: "http://example.org/StructureDefinition/TestEncounter",
+                    name: "TestEncounter",
+                    base: "http://hl7.org/fhir/StructureDefinition/Encounter",
+                    derivation: "constraint",
+                    kind: "resource",
+                    elements: {
+                        subject: {
+                            type: "Reference",
+                            refers: ["http://hl7.org/fhir/StructureDefinition/Patient"],
+                        },
+                    },
+                },
+                logger,
+            )
+        )[0] as ProfileTypeSchema;
+
+        const subject = ts.fields?.subject as RegularField;
+        expect(subject.reference?.resource.map((ref): string => ref.name)).toEqual(["Patient"]);
+        expect(subject.reference?.profiles).toBeUndefined();
+    });
+});