Index: Lib/collections.py
===================================================================
--- Lib/collections.py	(revision 70128)
+++ Lib/collections.py	(working copy)
@@ -23,11 +23,11 @@
         if len(args) > 1:
             raise TypeError('expected at most 1 arguments, got %d' % len(args))
         if not hasattr(self, '_keys'):
-            self._keys = []
+            self._keys = deque()
         self.update(*args, **kwds)
 
     def clear(self):
-        del self._keys[:]
+        self._keys.clear()
         dict.clear(self)
 
     def __setitem__(self, key, value):
@@ -52,6 +52,13 @@
         value = dict.pop(self, key)
         return key, value
 
+    def pop_oldest_item(self):
+        if not self:
+            raise KeyError('dictionary is empty')
+        key = self._keys.popleft()
+        value = dict.pop(self, key)
+        return key, value
+
     def __reduce__(self):
         items = [[k, self[k]] for k in self]
         inst_dict = vars(self).copy()
Index: Lib/test/test_collections.py
===================================================================
--- Lib/test/test_collections.py	(revision 70128)
+++ Lib/test/test_collections.py	(working copy)
@@ -665,6 +665,16 @@
             od.popitem()
         self.assertEqual(len(od), 0)
 
+    def test_pop_oldest_item(self):
+        pairs = [('c', 1), ('b', 2), ('a', 3), ('d', 4), ('e', 5), ('f', 6)]
+        shuffle(pairs)
+        od = OrderedDict(pairs)
+        while pairs:
+            self.assertEqual(od.pop_oldest_item(), pairs.pop(0))
+        with self.assertRaises(KeyError):
+            od.pop_oldest_item()
+        self.assertEqual(len(od), 0)
+
     def test_pop(self):
         pairs = [('c', 1), ('b', 2), ('a', 3), ('d', 4), ('e', 5), ('f', 6)]
         shuffle(pairs)