diff --git a/CHANGES.txt b/CHANGES.txt
index be1e1bb..721cd6e 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -11,6 +11,8 @@ Bug Fixes
 Features
 ~~~~~~~~
 
+- Add ``colander.Set`` type, ported from ``deform.Set``
+
 - Add Python 3.3 to tox configuration and use newer tox testing regime
   (setup.py dev).
 
diff --git a/CONTRIBUTORS.txt b/CONTRIBUTORS.txt
index 62357ae..35c6e72 100644
--- a/CONTRIBUTORS.txt
+++ b/CONTRIBUTORS.txt
@@ -107,4 +107,4 @@ Contributors
 - Atsushi Odagiri, 2012/02/04
 - Daniel Nouri, 2012/03/28
 - Gary van der Merwe, 2012/04/05
-- Domen Kožar, 2012-04-16
+- Domen Kožar, 2012/04/16
diff --git a/colander/__init__.py b/colander/__init__.py
index 20521c3..9424ebd 100644
--- a/colander/__init__.py
+++ b/colander/__init__.py
@@ -733,6 +733,40 @@ class Tuple(Positional, SchemaType):
         return appstruct[index]
 
 
+class Set(SchemaType):
+    """ A type representing a non-overlapping set of items.
+    Deserializes an iterable to a ``set`` object.
+
+    If the :attr:`colander.null` value is passed to the serialize
+    method of this class, the :attr:`colander.null` value will be
+    returned.
+
+    .. versionadded: 0.9.9.1
+
+    """
+
+    def serialize(self, node, appstruct):
+        if appstruct is null:
+            return null
+
+        return appstruct
+
+    def deserialize(self, node, cstruct):
+        if cstruct is null:
+            return null
+
+        if not hasattr(cstruct, '__iter__'):
+            raise Invalid(
+                node,
+                _('${cstruct} is not iterable', mapping={'cstruct': cstruct})
+            )
+
+        cstruct = set(cstruct)
+        if not cstruct:
+            return null
+        return cstruct
+
+
 class SequenceItems(list):
     """
     List marker subclass for use by Sequence.cstruct_children, which indicates
diff --git a/colander/tests/test_colander.py b/colander/tests/test_colander.py
index cc159e8..ccf5968 100644
--- a/colander/tests/test_colander.py
+++ b/colander/tests/test_colander.py
@@ -949,6 +949,52 @@ class TestTuple(unittest.TestCase):
         result = typ.cstruct_children(node1, ['one', 'two'])
         self.assertEqual(result, ['one', 'two'])
 
+
+class TestSet(unittest.TestCase):
+    def _makeOne(self, **kw):
+        from colander import Set
+        return Set(**kw)
+
+    def test_serialize(self):
+        typ = self._makeOne()
+        node = DummySchemaNode(typ)
+        provided = []
+        result = typ.serialize(node, provided)
+        self.assertTrue(result is provided)
+
+    def test_serialize_null(self):
+        from colander import null
+        typ = self._makeOne()
+        node = DummySchemaNode(typ)
+        result = typ.serialize(node, null)
+        self.assertTrue(result is null)
+
+    def test_deserialize_no_iter(self):
+        typ = self._makeOne()
+        node = DummySchemaNode(typ)
+        e = invalid_exc(typ.deserialize, node, 1)
+        self.assertEqual(e.msg, '${cstruct} is not iterable')
+
+    def test_deserialize_null(self):
+        from colander import null
+        typ = self._makeOne()
+        node = DummySchemaNode(typ)
+        result = typ.deserialize(node, null)
+        self.assertEqual(result, null)
+
+    def test_deserialize_valid(self):
+        typ = self._makeOne()
+        node = DummySchemaNode(typ)
+        result = typ.deserialize(node, ('a',))
+        self.assertEqual(result, set(('a',)))
+
+    def test_deserialize_empty_set(self):
+        import colander
+        typ = self._makeOne()
+        node = DummySchemaNode(typ)
+        result = typ.deserialize(node, set())
+        self.assertEqual(result, colander.null)
+
 class TestSequence(unittest.TestCase):
     def _makeOne(self, **kw):
         from colander import Sequence
diff --git a/docs/api.rst b/docs/api.rst
index c05dea3..c8471ae 100644
--- a/docs/api.rst
+++ b/docs/api.rst
@@ -74,6 +74,8 @@ Types
 
   .. autoclass:: Tuple
 
+  .. autoclass:: Set
+
   .. autoclass:: Sequence
 
   .. autoclass:: Seq