diff --git a/documentation/ref-manual/variables.rst b/documentation/ref-manual/variables.rst
index 2a97ff98d3f0cb178ab2b6463980cf5a354acfc5..1d4e2e2be67aab3ea22d1506be94c7222bbc6f53 100644
--- a/documentation/ref-manual/variables.rst
+++ b/documentation/ref-manual/variables.rst
@@ -1230,6 +1230,15 @@ system and gives an overview of their function and contents.
       :term:`Metadata` so it does not need to be parsed every time
       BitBake is started.
 
+   :term:`CARGO_INSTALL_LIBRARIES`
+      When inheriting the :ref:`ref-classes-cargo` class, the variable
+      :term:`CARGO_INSTALL_LIBRARIES` can be set to a non-empty value by
+      individual recipes to enable the installation of the libraries the
+      recipe has built in ``${B}/target/${CARGO_TARGET_SUBDIR}`` (files ending
+      with ``.so`` or ``.rlib``). By default this variable is not defined and
+      libraries are not installed, to replicate the behavior of the ``cargo
+      install`` command.
+
    :term:`CC`
       The minimal command and arguments used to run the C compiler.