diff --git a/CHANGELOG.md b/CHANGELOG.md
index d79d90b..d3f1d55 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,7 @@
 
 (in development)
 ================
+* Make the PySide6 version compatibility constraint optional through the `pyside6` extra.
 * `QModelIndex.constInternalPointer()` should be `Any`
 * `QDBusConnection.internalPointer()` and `QDBusConnection.constInternalPointer()` should be `Any`
 * `QInputDialog.getText()`, `getInt()`, `getFloat()`, `getMultiLineText()`, `getItem()` accept `None`as parent argument
diff --git a/README.md b/README.md
index e6a8b24..53c4949 100644
--- a/README.md
+++ b/README.md
@@ -44,10 +44,18 @@ As a derived work from PySide6, the stubs are delivered under the LGPL v2.1 . Se
 
 # Installation
 
-Install from pypi:
+Install the stubs with pip:
 
     $ pip install PySide6-stubs
 
+To have the dependency resolver enforce the declared PySide6 version
+compatibility constraints, select the `pyside6` extra:
+
+    $ pip install "PySide6-stubs[pyside6]"
+
+Selecting this extra may also cause pip to install or change PySide6 as a side
+effect of satisfying those constraints.
+
 
 If you want to install the stable development version from the Git repository:
 
diff --git a/setup.cfg b/setup.cfg
index 4e4fec1..46c8c38 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -25,8 +25,6 @@ package_dir =
    shiboken6-stubs = shiboken6-stubs
 
 python_requires = >=3.7
-install_requires =
-    PySide6>=6.0
 
 [options.package_data]
 * = *.pyi
@@ -37,6 +35,8 @@ exclude =
 
 
 [options.extras_require]
+pyside6 =
+    PySide6>=6.0
 dev =
     pytest
     mypy>=1.0
\ No newline at end of file