diff --git a/src/pyoctaveband/__init__.py b/src/pyoctaveband/__init__.py
index 422dbdf..0524992 100644
--- a/src/pyoctaveband/__init__.py
+++ b/src/pyoctaveband/__init__.py
@@ -8,7 +8,6 @@
 
 from typing import List, Tuple, overload, Literal
 
-import matplotlib
 import numpy as np
 
 from .calibration import calculate_sensitivity
@@ -17,9 +16,6 @@
 from .parametric_filters import WeightingFilter, linkwitz_riley, time_weighting, weighting_filter
 from ._version import __version__
 
-# Use non-interactive backend for plots
-matplotlib.use("Agg")
-
 # Public methods
 __all__ = [
     "__version__",
diff --git a/src/pyoctaveband/_version.py b/src/pyoctaveband/_version.py
index bc86c94..10aa336 100644
--- a/src/pyoctaveband/_version.py
+++ b/src/pyoctaveband/_version.py
@@ -1 +1 @@
-__version__ = "1.2.2"
+__version__ = "1.2.3"
diff --git a/tests/conftest.py b/tests/conftest.py
index 74d3d1a..d737c7c 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -2,6 +2,13 @@
 import os
 import pytest
 
+# Select a non-interactive matplotlib backend for the headless test suite.
+# The library no longer forces a backend (see issue #52), so the test harness
+# must opt into Agg itself; otherwise matplotlib picks a GUI backend (e.g.
+# TkAgg on Windows runners) and figure creation fails without a display/Tcl.
+# Set at import time so it takes effect before any test module imports pyplot.
+os.environ.setdefault("MPLBACKEND", "Agg")
+
 def pytest_configure(config):
     """
     Configure environment variables for the test session.
diff --git a/tests/test_matplotlib_backend.py b/tests/test_matplotlib_backend.py
new file mode 100644
index 0000000..af1d823
--- /dev/null
+++ b/tests/test_matplotlib_backend.py
@@ -0,0 +1,38 @@
+#  Copyright (c) 2026. Jose M. Requena-Plens
+
+"""
+Tests ensuring the package does not hijack the global matplotlib backend.
+
+Importing pyoctaveband must not force a specific (e.g. non-interactive)
+backend, so the package can be used during interactive exploration
+(IPython, Jupyter). See issue #52.
+"""
+
+import os
+import subprocess
+import sys
+
+
+def test_import_does_not_override_matplotlib_backend() -> None:
+    """Importing pyoctaveband must preserve the user's chosen backend."""
+    code = (
+        "import matplotlib\n"
+        # Pick an explicit, always-available backend the user might have set.
+        "matplotlib.use('svg')\n"
+        "before = matplotlib.get_backend()\n"
+        "import pyoctaveband\n"
+        "after = matplotlib.get_backend()\n"
+        "assert before == after, f'backend changed: {before!r} -> {after!r}'\n"
+    )
+    # Propagate the parent's sys.path so the subprocess can import the package
+    # even when it is only on sys.path (e.g. pytest without an installed build).
+    env = os.environ.copy()
+    env["PYTHONPATH"] = os.pathsep.join(sys.path)
+    result = subprocess.run(
+        [sys.executable, "-c", code],
+        capture_output=True,
+        text=True,
+        env=env,
+        timeout=30,
+    )
+    assert result.returncode == 0, result.stderr