diff --git a/README.md b/README.md
index 2168ccb..1b7013a 100644
--- a/README.md
+++ b/README.md
@@ -30,8 +30,55 @@ Use `eessi --help` to get basic usage information.
 
 Check CernVM-FS setup for accessing EESSI
 
-*(to be implemented)*
+```shell
+eessi check
+```
 
+Example output:
+```
+📦 Checking for EESSI repositories...
+    ✅ OK /cvmfs/dev.eessi.io is available
+    ✅ OK /cvmfs/riscv.eessi.io is available
+    ✅ OK /cvmfs/software.eessi.io is available
+
+🔎 Inspecting EESSI repository software.eessi.io...
+    💻 Client cache:
+        ℹ Path to client cache directory: /var/lib/cvmfs/shared
+        ℹ Shared cache: yes
+        ℹ Client cache quota limit: 9.765625 GiB
+        ℹ Cache Usage:  282k / 10240001k
+    🌍 Server/proxy settings:
+        ℹ List of Stratum-1 mirror servers:
+            http://aws-eu-central-s1.eessi.science/cvmfs/software.eessi.io
+            http://azure-us-east-s1.eessi.science/cvmfs/software.eessi.io
+            http://cvmfs-ext.gridpp.rl.ac.uk:8000/cvmfs/software.eessi.io
+        ⚡ WARNING Proxy servers: DIRECT (not recommended, see https://eessi.io/docs/no-proxy)
+        ℹ GeoAPI enabled: yes
+    💁 Other:
+        ℹ Client profile:
+```
+
+If CernVM-FS is not available at all:
+```
+eessi check
+📦 Checking for EESSI repositories...
+    ❌ ERROR /cvmfs/dev.eessi.io is NOT available
+    ❌ ERROR /cvmfs/riscv.eessi.io is NOT available
+    ❌ ERROR /cvmfs/software.eessi.io is NOT available
+
+🔎 Inspecting EESSI repository software.eessi.io...
+    💻 Client cache:
+        ℹ Path to client cache directory:  UNKNOWN
+        ℹ Shared cache:  UNKNOWN
+        ℹ Client cache quota limit:  UNKNOWN
+        ❌ ERROR Required field 'Cache Usage' not found!
+    🌍 Server/proxy settings:
+        ℹ List of Stratum-1 mirror servers:  UNKNOWN
+        ℹ Proxy servers:  UNKNOWN
+        ℹ GeoAPI enabled:  UNKNOWN
+    💁 Other:
+        ℹ Client profile:  UNKNOWN
+```
 
 ### `init` subcommand
 
diff --git a/src/eessi/cli/check.py b/src/eessi/cli/check.py
index 6f37bd6..1571863 100644
--- a/src/eessi/cli/check.py
+++ b/src/eessi/cli/check.py
@@ -2,13 +2,255 @@
 #
 # authors: Kenneth Hoste (Ghent University)
 
+import os
+import re
+import subprocess
+
 import typer
+from rich import print as rich_print
 
 from eessi.cli.help import help_callback
 
 app = typer.Typer()
 
 
+INFO = 'INFO'
+OK = 'OK'
+WARNING = 'WARNING'
+ERROR = 'ERROR'
+
+UNKNOWN = '[bold yellow] UNKNOWN'
+
+CVMFS_ROOT = '/cvmfs'
+
+CVMFS_CLIENT_SETTINGS = {
+    # TODO: warn if path of client cache dir is in /tmp
+    'CVMFS_CACHE_DIR': "Path to client cache directory",
+    'CVMFS_CLIENT_PROFILE': "Client profile",
+    # TODO: warn if there's only one
+    'CVMFS_HTTP_PROXY': "Proxy servers",
+    # TODO: warn if too small? (<1GB)
+    'CVMFS_QUOTA_LIMIT': "Client cache quota limit",
+    # TODO: warn if there's only one (and no proxies)
+    'CVMFS_SERVER_URL': "List of Stratum-1 mirror servers",
+    'CVMFS_SHARED_CACHE': "Shared cache",
+    'CVMFS_USE_GEOAPI': "GeoAPI enabled",
+}
+
+# development repo with various sub-projects
+# see also https://www.eessi.io/docs/repositories/dev.eessi.io
+EESSI_DEV_REPO = 'dev.eessi.io'
+
+# experimental repo for RISC-V,
+# see also https://www.eessi.io/docs/repositories/riscv.eessi.io
+EESSI_RISCV_REPO = 'riscv.eessi.io'
+
+# main production repo,
+# see also https://www.eessi.io/docs/repositories/software.eessi.io
+EESSI_SOFTWARE_REPO = 'software.eessi.io'
+
+EESSI_REPOS = [
+    EESSI_DEV_REPO,
+    EESSI_RISCV_REPO,
+    EESSI_SOFTWARE_REPO,
+]
+
+
+def print_result(status: str, msg: str, indent_level: int = 0):
+    """
+    Print result for a specific check
+    """
+    indent = indent_level * 4 * ' '
+
+    if status == OK:
+        rich_print(f"{indent}:white_check_mark: {status} {msg}")
+    elif status == INFO:
+        rich_print(f"{indent}:information: {msg}")
+    elif status == WARNING:
+        rich_print(f"{indent}:zap: [yellow]{status} {msg}")
+    elif status == ERROR:
+        rich_print(f"{indent}:x: [bold red]{status} {msg}")
+    else:
+        rich_print(f"{indent}:{status}: {msg}")
+
+def run_cmd(cmd: str):
+    """
+    Run shell command.
+
+    Returns stdout, stderr, and exit code.
+    """
+    res = subprocess.run(cmd, shell=True, capture_output=True, universal_newlines=True)
+
+    return (res.stdout, res.stderr, res.returncode)
+
+
+def is_repo_available(repo: str):
+    """
+    Check if repo is available
+    """
+    repo_path = os.path.join(CVMFS_ROOT, repo)
+    if os.path.isdir(repo_path):
+        res = (OK, f"{repo_path} is available")
+    else:
+        res = (ERROR, f"{repo_path} is NOT available")
+
+    return res
+
+
+def get_repo_attribute(repo: str, key: str):
+    """
+    Get repository attribute
+    """
+    repo_path = os.path.join(CVMFS_ROOT, repo)
+    (stdout, stderr, exit_code) = run_cmd(f"attr -g {key} {repo_path}")
+    if exit_code == 0:
+        # expected output is something like:
+        # Attribute "revision" had a 5 byte value for /cvmfs/software.eessi.io:
+        # 13972
+        value = stdout.splitlines()[-1]
+    else:
+        value = UNKNOWN
+
+    return value
+
+
+def get_cvmfs_config_settings(repo: str, keys: list[str]):
+    """
+    Get values for specific CernVM-FS configuration settings
+    """
+    cmd = f"cvmfs_config showconfig {repo}"
+    (stdout, stderr, exit_code) = run_cmd(cmd)
+
+    values = {}
+    for key in keys:
+        regex = re.compile(f'^{key}=(?P<value>.*)', re.M)
+        res = regex.search(stdout)
+        if res:
+            # value may be a list of items, like:
+            # CVMFS_SERVER_URL='http://server.one;http://server.two' . # from /etc/cvmfs/default.local
+
+            # cut off comment at the end
+            value = res.group('value').split('#', 1)[0].rstrip()
+            # strip single quotes at start/end
+            value = value.strip("'")
+            # split by semicolon for list values
+            if ';' in value:
+                value = value.split(';')
+
+            values[key] = value
+        else:
+            values[key] = UNKNOWN
+
+    return values
+
+
+def reformat_for_humans(key: str, value: str):
+    """
+    Reformat value for specific CernVM-FS configuration setting for humans
+    """
+    if key == 'CVMFS_QUOTA_LIMIT' and value != UNKNOWN:
+        gb = int(value) / 1024.
+        value = f"{gb} GiB"
+
+    return value
+
+
+def check_repo(repo: str):
+    """
+    Checks for specified CernVM-FS repository
+    """
+    repo_path = os.path.join(CVMFS_ROOT, repo)
+
+    results = [
+        is_repo_available(repo),
+    ]
+
+    revision = get_repo_attribute(repo, 'revision')
+    status = ERROR if revision == UNKNOWN else INFO
+    results.append((status, f"Revision (client): {revision}"))
+
+    grouped_keys = {
+        "Client cache": {
+            'sigil': 'computer',
+            'keys': ['CVMFS_CACHE_DIR', 'CVMFS_SHARED_CACHE', 'CVMFS_QUOTA_LIMIT'],
+            'stat_fields': ["Cache Usage"],
+        },
+        "Server/proxy settings": {
+            'sigil': 'globe_showing_europe-africa',
+            'keys': ['CVMFS_SERVER_URL', 'CVMFS_HTTP_PROXY', 'CVMFS_USE_GEOAPI'],
+        },
+        "Other": {
+            'sigil': 'information_desk_person',
+            'keys': ['CVMFS_CLIENT_PROFILE'],
+        },
+    }
+
+    cmd = f"cvmfs_config stat -v {repo}"
+    stat_output, stderr, exit_code = run_cmd(cmd)
+    if exit_code:
+        # 'cvmfs_config stat' failed, just ignore here
+        stat_output = ''
+
+    for descr, specs in grouped_keys.items():
+        print_result(specs['sigil'], f"{descr}:", indent_level=1)
+
+        setting_values = get_cvmfs_config_settings(repo, specs['keys'])
+
+        for key in specs['keys']:
+            descr = CVMFS_CLIENT_SETTINGS[key]
+            value = setting_values.get(key)
+            value = reformat_for_humans(key, value)
+
+            status = INFO
+            if key == 'CVMFS_HTTP_PROXY' and value == 'DIRECT':
+                status = WARNING
+                value += " (not recommended, see https://eessi.io/docs/no-proxy)"
+
+            if value is None:
+                results.append((ERROR, f"{descr}: {UNKNOWN}"))
+            else:
+                if isinstance(value, list):
+                    # indent list items by two levels
+                    value = '\n' + '\n'.join(' ' * 4 * 3 + x for x in value)
+
+                print_result(status, f"{descr}: {value}", indent_level=2)
+
+        for field in specs.get('stat_fields', []):
+            regex = re.compile(f"^{field}:(?P<value>.*)", re.M)
+            res = regex.search(stat_output)
+            if res:
+                print_result(INFO, f"{field}: {res.group('value')}", indent_level=2)
+            else:
+                print_result(ERROR, f"Required field '{field}' not found!", indent_level=2)
+
+    ncleanup24 = get_repo_attribute(repo, 'ncleanup24')
+    msg = f"Number of cache cleanups in last 24h: {ncleanup24}"
+    if ncleanup24 == UNKNOWN:
+        status = ERROR
+    else:
+        ncleanup24 = int(ncleanup24)
+        
+        if ncleanup24 > 24:
+            status = WARNING
+            msg += " (cache quota limit too low?)"
+        else:
+            status = OK
+    results.append((status, msg))
+
+
+    return results
+
+
+# TODO:
+# download manifest from mirror:
+# http://aws-eu-central-s1.eessi.science/cvmfs/software.eessi.io/.cvmfspublished
+# with open('manifest', mode='rb') as fp:
+#   manifest = fp.read()
+# >>> [x for x in manifest.splitlines() if x.startswith(b'S')]
+# [b'S13972']
+# timestamp of revsion from server manifest: T1769765986
+
+
 @app.command()
 def check(
     help: bool = typer.Option(
@@ -23,4 +265,11 @@ def check(
     """
     Check CernVM-FS setup for accessing EESSI
     """
-    raise NotImplementedError
+    rich_print(":package: Checking for EESSI repositories...")
+    for repo in EESSI_REPOS:
+        print_result(*is_repo_available(repo), indent_level=1)
+    print('')
+
+    repo = EESSI_SOFTWARE_REPO
+    rich_print(f":magnifying_glass_tilted_right: Inspecting EESSI repository {repo}...")
+    check_repo(repo=repo)