diff --git a/README b/README
index a86f8a3..8cb2f93 100644
--- a/README
+++ b/README
@@ -249,3 +249,11 @@ MELLON_ERROR_REDIRECT_AFTER_TIMEOUT
 
 Timeout in seconds before automatically redirecting the user to the
 continue URL when authentication has failed. Default is 120 seconds.
+
+
+Tests
+=====
+
+Unit tests are written using pytest, and can be run with:
+
+   DJANGO_SETTINGS_MODULE=testsettings py.test
diff --git a/mellon/tests.py b/mellon/tests.py
deleted file mode 100644
index fd9358c..0000000
--- a/mellon/tests.py
+++ /dev/null
@@ -1,7 +0,0 @@
-from django.test import TestCase
-
-# Create your tests here.
-
-class MellonTestCase(TestCase):
-    def test_coin(self):
-        pass
diff --git a/tests/test_default_adapter.py b/tests/test_default_adapter.py
new file mode 100644
index 0000000..0f910da
--- /dev/null
+++ b/tests/test_default_adapter.py
@@ -0,0 +1,79 @@
+import pytest
+
+from django.conf import settings
+from django.contrib import auth
+
+from mellon.adapters import DefaultAdapter
+
+pytestmark = pytest.mark.django_db
+
+idp = {}
+saml_attributes = {
+    'name_id_content': 'x'*32,
+    'issuer': 'https://idp.example.net/saml/metadata',
+    'username': ['foobar'],
+    'email': ['test@example.net'],
+    'first_name': ['Foo'],
+    'last_name': ['Bar'],
+    'is_superuser': ['true'],
+}
+
+def test_format_username(settings):
+    adapter = DefaultAdapter()
+    assert adapter.format_username(idp, {}) == None
+    assert adapter.format_username(idp, saml_attributes) == 'x'*32 + '@saml'
+    settings.MELLON_USERNAME_TEMPLATE = '{attributes[name_id_content]}'
+    assert adapter.format_username(idp, saml_attributes) == 'x'*32
+    settings.MELLON_USERNAME_TEMPLATE = '{attributes[username][0]}'
+    assert adapter.format_username(idp, saml_attributes) == 'foobar'
+
+def test_lookup_user(settings):
+    User = auth.get_user_model()
+    adapter = DefaultAdapter()
+    user = adapter.lookup_user(idp, saml_attributes)
+    assert user is not None
+
+    user2 = adapter.lookup_user(idp, saml_attributes)
+    assert user.id == user2.id
+
+    User.objects.all().delete()
+    assert User.objects.count() == 0
+
+    settings.MELLON_PROVISION = False
+    user = adapter.lookup_user(idp, saml_attributes)
+    assert user is None
+    assert User.objects.count() == 0
+
+def test_provision(settings):
+    User = auth.get_user_model()
+    adapter = DefaultAdapter()
+    settings.MELLON_ATTRIBUTE_MAPPING = {
+        'email': '{attributes[email][0]}',
+        'first_name': '{attributes[first_name][0]}',
+        'last_name': '{attributes[last_name][0]}',
+    }
+    user = User(username='xx')
+    user.save()
+    adapter.provision(user, idp, saml_attributes)
+    assert user.first_name == 'Foo'
+    assert user.last_name == 'Bar'
+    assert user.email == 'test@example.net'
+    assert user.is_superuser == False
+    User.objects.all().delete()
+
+    settings.MELLON_SUPERUSER_MAPPING = {
+        'is_superuser': 'true',
+    }
+    user = User(username='xx')
+    user.save()
+    adapter.provision(user, idp, saml_attributes)
+    assert user.is_superuser == True
+    User.objects.all().delete()
+
+    local_saml_attributes = saml_attributes.copy()
+    del local_saml_attributes['email']
+    user = User(username='xx')
+    user.save()
+    adapter.provision(user, idp, local_saml_attributes)
+    assert not user.email
+    User.objects.all().delete()