diff --git a/tests/unit/test_cassettes.py b/tests/unit/test_cassettes.py
index d2b09fa..2df0e76 100644
--- a/tests/unit/test_cassettes.py
+++ b/tests/unit/test_cassettes.py
@@ -1,12 +1,59 @@
+import mock
 import yaml
 from vcr.cassette import Cassette
 
 def test_cassette_load(tmpdir):
     a_file = tmpdir.join('test_cassette.yml')
-    a_file.write(yaml.dumps([
+    a_file.write(yaml.dump([
         {'request':'foo', 'response':'bar'}
     ]))
-    a_cassette = Cassette.load(a_file)
+    a_cassette = Cassette.load(str(a_file))
     assert a_cassette._requests
     assert a_cassette._responses
 
+def test_cassette_serialize():
+    a = Cassette('test')
+    a._requests = ['foo']
+    a._responses = ['bar']
+    assert a.serialize() == [{'request': 'foo', 'response': 'bar'}]
+
+def test_cassette_deserialize():
+    a = Cassette('test')
+    a.deserialize([{'request': 'foo', 'response': 'bar'}])
+    assert a._requests == ['foo']
+    assert a._responses == ['bar']
+
+def test_cassette_not_cached():
+    a = Cassette('test')
+    assert not a.cached()
+
+def test_cassette_cached():
+    a = Cassette('test')
+    a.cached('yup')
+    assert a.cached()
+
+def test_cassette_append():
+    a = Cassette('test')
+    a.append('foo', 'bar')
+    assert a._requests == ['foo']
+    assert a._responses == ['bar']
+
+def test_cassette_len():
+    a = Cassette('test')
+    a.append('foo','bar')
+    a.append('foo2','bar2')
+    assert len(a) == 2
+
+def test_cassette_contains():
+    a = Cassette('test')
+    a.append('foo','bar')
+    assert 'foo' in a
+
+def test_cassette_response():
+    a = Cassette('test')
+    a.append('foo','bar')
+    assert a.response('foo') == 'bar'
+
+def test_cassette_missing_response():
+    a = Cassette('test')
+    assert a.response('foo')