Index: Doc/library/tarfile.rst
===================================================================
--- Doc/library/tarfile.rst	(revision 78438)
+++ Doc/library/tarfile.rst	(working copy)
@@ -676,7 +676,14 @@
     tar.add("foo", filter=reset)
     tar.close()
 
+How to use :func:`tarfile.open` as a context manager 
+(see :ref:`typecontextmanager`)::
 
+    import tarfile
+    with tarfile.open("sample.tar.gz", "w") as tar:
+        for file in ("file1", "file2"):
+            tar.add(file)
+
 .. _tar-formats:
 
 Supported tar formats
@@ -756,4 +763,3 @@
 representation. This is the default scheme. In write mode the default value for
 *errors* is ``'strict'`` to ensure that name information is not altered
 unnoticed.
-
Index: Lib/tarfile.py
===================================================================
--- Lib/tarfile.py	(revision 78438)
+++ Lib/tarfile.py	(working copy)
@@ -2411,6 +2411,16 @@
         """
         if level <= self.debug:
             print >> sys.stderr, msg
+
+    def __enter__(self):
+        """Enter the runtime context.
+        """
+        return self
+
+    def __exit__(self, type, value, traceback):
+        """Exit the runtime context without supressing any exceptions.
+        """
+        self.close()
 # class TarFile
 
 class TarIter:
Index: Lib/test/test_tarfile.py
===================================================================
--- Lib/test/test_tarfile.py	(revision 78438)
+++ Lib/test/test_tarfile.py	(working copy)
@@ -327,7 +327,23 @@
         finally:
             os.remove(empty)
 
+    def test_context_manager(self):
+        # tarfile can be used as a context manager
+        with tarfile.open(tarname) as tar:
+            self.assertFalse(tar.closed)
+        self.assertTrue(tar.closed)
 
+    def test_context_manager_exception(self):
+        try:
+            # tarfile can be used as a context manager
+            with tarfile.open(tarname) as tar:
+                self.assertFalse(tar.closed)
+                raise Exception
+        except:
+            self.assertTrue(tar.closed)
+        else:
+            self.fail("Exception not reraised.")
+
 class StreamReadTest(CommonReadTest):
 
     mode="r|"