Index: Modules/cStringIO.c
===================================================================
--- Modules/cStringIO.c	(revision 60906)
+++ Modules/cStringIO.c	(working copy)
@@ -477,6 +477,35 @@
 
        Py_RETURN_NONE;
 }
+
+PyDoc_STRVAR(IO_enter__doc__,
+	     "__enter__() -> self.");
+static PyObject *
+IO_enter(IOobject *self)
+{
+	if (!IO__opencheck(self))
+		return NULL;
+	Py_INCREF(self);
+	return (PyObject *)self;
+}
+
+PyDoc_STRVAR(IO_exit__doc__,
+	     "__exit__(*excinfo) -> None.  Calls close().");
+
+static PyObject *
+IO_exit(PyObject *self, PyObject *args)
+{
+	PyObject *ret = PyObject_CallMethod(self, "close", NULL);
+	if (!ret)
+		/* If error occurred, pass through */
+		return NULL;
+	Py_DECREF(ret);
+	/* We cannot return the result of close since a true
+	 * value will be interpreted as "yes, swallow the
+	 * exception if one was raised inside the with block". */
+	Py_RETURN_NONE;
+}
+
 static struct PyMethodDef O_methods[] = {
   /* Common methods: */
   {"flush",     (PyCFunction)IO_flush,    METH_NOARGS,  IO_flush__doc__},
@@ -494,6 +523,11 @@
   {"seek",       (PyCFunction)O_seek,       METH_VARARGS, O_seek__doc__},
   {"write",	 (PyCFunction)O_write,      METH_VARARGS, O_write__doc__},
   {"writelines", (PyCFunction)O_writelines, METH_O,	  O_writelines__doc__},
+
+  /* Context management methods: */
+  {"__enter__", (PyCFunction)IO_enter,     METH_NOARGS, IO_enter__doc__},
+  {"__exit__",  (PyCFunction)IO_exit,     METH_VARARGS, IO_exit__doc__},
+
   {NULL,	 NULL}		/* sentinel */
 };
 
Index: Lib/StringIO.py
===================================================================
--- Lib/StringIO.py	(revision 60906)
+++ Lib/StringIO.py	(working copy)
@@ -62,6 +62,16 @@
         self.closed = False
         self.softspace = 0
 
+    # Context management protocol
+    def __enter__(self):
+        if self.closed:
+            raise ValueError("I/O operation on closed file")
+        return self
+
+    def __exit__(self, exc, value, tb):
+        self.close()
+
+    # file protocol
     def __iter__(self):
         return self
 
Index: Lib/test/test_StringIO.py
===================================================================
--- Lib/test/test_StringIO.py	(revision 60906)
+++ Lib/test/test_StringIO.py	(working copy)
@@ -118,6 +118,15 @@
         self.assertEqual(s, unicode('abcuvwxyz!'))
         self.assertEqual(type(s), types.UnicodeType)
 
+    def test_context_management(self):
+        with self.MODULE.StringIO() as f:
+            self.failIf(f.closed)
+        self.failUnless(f.closed)
+        def use_closed():
+            with f:
+                pass
+        self.failUnlessRaises(ValueError, use_closed)
+
 class TestcStringIO(TestGenericStringIO):
     MODULE = cStringIO