diff --git a/beets/attachments.py b/beets/attachments.py
index f13f7db16..13324e88e 100644
--- a/beets/attachments.py
+++ b/beets/attachments.py
@@ -24,6 +24,12 @@ from beets import dbcore
 
 
 class Attachment(dbcore.db.Model):
+    """Represents an attachment in the database.
+
+    An attachment has four properties that correspond to fields in the
+    database: ``url``, ``type``, ``ref``, and ``ref_type``. Flexible
+    attributes are accessed as ``attachment[key]``.
+    """
 
     _fields = {
         'url':      dbcore.types.String(),
diff --git a/test/test_attachments.py b/test/test_attachments.py
new file mode 100644
index 000000000..8305b42a3
--- /dev/null
+++ b/test/test_attachments.py
@@ -0,0 +1,53 @@
+# This file is part of beets.
+# Copyright 2014, Thomas Scholtes
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+
+
+from _common import unittest
+
+from beets.attachments import AttachmentFactory
+from beets.library import Library, Album
+
+class AttachmentFactoryTest(unittest.TestCase):
+
+    def setUp(self):
+        self.lib = Library(':memory:')
+        self.factory = AttachmentFactory(self.lib)
+
+    def test_create(self):
+        attachment = self.factory.create('/path/to/attachment', 'coverart')
+        self.assertEqual(attachment.url, '/path/to/attachment')
+        self.assertEqual(attachment.type, 'coverart')
+
+    def test_create_sets_entity(self):
+        album = Album()
+        album.add(self.lib)
+        attachment = self.factory.create('/path/to/attachment', 'coverart',
+                                         entity=album)
+        self.assertEqual(attachment.ref, album.id)
+        self.assertEqual(attachment.ref_type, 'album')
+
+    def test_create_populates_metadata(self):
+        def collector(type, url):
+            return {'mime': 'image/'}
+        self.factory.register_collector(collector)
+
+        attachment = self.factory.create('/path/to/attachment', 'coverart')
+        self.assertEqual(attachment['mime'], 'image/')
+
+
+def suite():
+    return unittest.TestLoader().loadTestsFromName(__name__)
+
+if __name__ == '__main__':
+    unittest.main(defaultTest='suite')