diff --git a/mopidy/local/__init__.py b/mopidy/local/__init__.py
index 104c43af..725e6783 100644
--- a/mopidy/local/__init__.py
+++ b/mopidy/local/__init__.py
@@ -99,11 +99,9 @@ class Library(object):
         """
         Lookup the given URI.
 
-        Unlike the core APIs, local tracks uris can only be resolved to a
-        single track.
-
         :param string uri: track URI
-        :rtype: :class:`~mopidy.models.Track`
+        :rtype: List of :class:`~mopidy.models.Track` or single
+        :class:`~mopidy.models.Track` for backward compatibility
         """
         raise NotImplementedError
 
diff --git a/mopidy/local/json.py b/mopidy/local/json.py
index 5ae04592..30fbb562 100644
--- a/mopidy/local/json.py
+++ b/mopidy/local/json.py
@@ -151,9 +151,9 @@ class JsonLibrary(local.Library):
 
     def lookup(self, uri):
         try:
-            return self._tracks[uri]
+            return [self._tracks[uri]]
         except KeyError:
-            return None
+            return []
 
     def search(self, query=None, limit=100, offset=0, uris=None, exact=False):
         tracks = self._tracks.values()
diff --git a/mopidy/local/library.py b/mopidy/local/library.py
index a4645084..ec5f4869 100644
--- a/mopidy/local/library.py
+++ b/mopidy/local/library.py
@@ -33,11 +33,13 @@ class LocalLibraryProvider(backend.LibraryProvider):
     def lookup(self, uri):
         if not self._library:
             return []
-        track = self._library.lookup(uri)
-        if track is None:
+        tracks = self._library.lookup(uri)
+        if tracks is None:
             logger.debug('Failed to lookup %r', uri)
             return []
-        return [track]
+        if isinstance(tracks, models.Track):
+            tracks = [tracks]
+        return tracks
 
     def find_exact(self, query=None, uris=None):
         if not self._library:
diff --git a/tests/local/test_library.py b/tests/local/test_library.py
index fcc6d4df..148c82e5 100644
--- a/tests/local/test_library.py
+++ b/tests/local/test_library.py
@@ -5,6 +5,8 @@ import shutil
 import tempfile
 import unittest
 
+import mock
+
 import pykka
 
 from mopidy import core
@@ -129,6 +131,22 @@ class LocalLibraryProviderTest(unittest.TestCase):
         tracks = self.library.lookup('fake uri')
         self.assertEqual(tracks, [])
 
+    # test backward compatibility with local libraries returning a
+    # single Track
+    @mock.patch.object(json.JsonLibrary, 'lookup')
+    def test_lookup_return_single_track(self, mock_lookup):
+        backend = actor.LocalBackend(config=self.config, audio=None)
+
+        mock_lookup.return_value = self.tracks[0]
+        tracks = backend.library.lookup(self.tracks[0].uri)
+        mock_lookup.assert_called_with(self.tracks[0].uri)
+        self.assertEqual(tracks, self.tracks[0:1])
+
+        mock_lookup.return_value = None
+        tracks = backend.library.lookup('fake uri')
+        mock_lookup.assert_called_with('fake uri')
+        self.assertEqual(tracks, [])
+
     # TODO: move to search_test module
     def test_find_exact_no_hits(self):
         result = self.library.find_exact(track_name=['unknown track'])