diff --git a/Doc/c-api/init.rst b/Doc/c-api/init.rst
index 4fb428dbd4b394f1f691fa61c52560d06c471144..2f0f20ff18e061995c3fc5b1ccfdba022e08367c 100644
--- a/Doc/c-api/init.rst
+++ b/Doc/c-api/init.rst
@@ -374,6 +374,10 @@ Initialization, Finalization, and Threads
    Set the default "home" directory, that is, the location of the standard
    Python libraries.  The libraries are searched in
    :file:`{home}/lib/python{version}` and :file:`{home}/lib/python{version}`.
+   The argument should point to a zero-terminated character string in static
+   storage whose contents will not change for the duration of the program's
+   execution.  No code in the Python interpreter will change the contents of
+   this storage.
 
 
 .. cfunction:: char* Py_GetPythonHome()