diff -r ed590800fde7 Lib/enum.py
--- a/Lib/enum.py	Sun Sep 15 10:37:57 2013 +0200
+++ b/Lib/enum.py	Sun Sep 15 23:08:11 2013 +0800
@@ -222,6 +222,17 @@
     def __contains__(cls, member):
         return isinstance(member, cls) and member.name in cls._member_map_
 
+    def __delattr__(cls, attr):
+        if attr in cls._member_map_:
+            raise TypeError("Cannot delete attribute")
+        super(EnumMeta, cls).__delattr__(attr)
+
+    def __delitem__(cls, key):
+        if key in cls._member_map_:
+            raise TypeError("Cannot delete item")
+        else:
+            raise KeyError(key)
+
     def __dir__(self):
         return ['__class__', '__doc__', '__members__'] + self._member_names_
 
diff -r ed590800fde7 Lib/test/test_enum.py
--- a/Lib/test/test_enum.py	Sun Sep 15 10:37:57 2013 +0200
+++ b/Lib/test/test_enum.py	Sun Sep 15 23:08:11 2013 +0800
@@ -1003,6 +1003,29 @@
             yellow = 6
         self.assertEqual(MoreColor.magenta.hex(), '5 hexlified!')
 
+    def test_attribute_deletion(self):
+        class Season(Enum):
+            SPRING = 1
+            SUMMER = 2
+            AUTUMN = 3
+            WINTER = 4
+
+            def spam(cls): pass
+
+        self.assertTrue(hasattr(Season, 'spam'))
+        del Season.spam
+        self.assertFalse(hasattr(Season, 'spam'))
+
+        with self.assertRaises(TypeError):
+            del Season.SPRING
+        with self.assertRaises(TypeError):
+            del Season['SPRING']
+        with self.assertRaises(AttributeError):
+            del Season.DRY
+        with self.assertRaises(KeyError):
+            del Season['DRY']
+        with self.assertRaises(AttributeError):
+            del Season.SPRING.name
 
     def test_no_duplicates(self):
         class UniqueEnum(Enum):