diff --git a/Doc/library/stringio.rst b/Doc/library/stringio.rst
index 4736fc3..19e1547 100644
--- a/Doc/library/stringio.rst
+++ b/Doc/library/stringio.rst
@@ -37,7 +37,8 @@
 
 .. method:: StringIO.close()
 
-   Free the memory buffer.
+   Free the memory buffer.  Attempting to do further operations with a closed
+   :class:`StringIO` object will raise a :exc:`ValueError`.
 
 Example usage::