diff --git a/Doc/library/venv.rst b/Doc/library/venv.rst
index 1ad2401fe2f3f31..9d4c53de7a50291 100644
--- a/Doc/library/venv.rst
+++ b/Doc/library/venv.rst
@@ -144,6 +144,8 @@ The command, if run with ``-h``, will show the available options::
 .. option:: --prompt <PROMPT>
 
    Provides an alternative prompt prefix for this environment.
+   Depending on the operating system, the prompt string may be
+   evaluated by the shell.
 
 .. option:: --upgrade-deps