diff --git a/controller/Files.py b/controller/Files.py
index 7c54ca7..bd63757 100644
--- a/controller/Files.py
+++ b/controller/Files.py
@@ -560,8 +560,8 @@ class Files( object ):
 
     @type note: model.Note
     @param note: note to search for file links
-    @type ignore_file_links: bool
-    @param ignore_file_links: if True, delete all files that are/were linked from this note
+    @type purge_all_links: bool
+    @param purge_all_links: if True, delete all files that are/were linked from this note
     """
     # load metadata for all files with the given note's note_id 
     files = self.__database.select_many( File, File.sql_load_note_files( note.object_id ) )
diff --git a/controller/test/Test_files.py b/controller/test/Test_files.py
index 0f4ec5d..de1865b 100644
--- a/controller/test/Test_files.py
+++ b/controller/test/Test_files.py
@@ -1,5 +1,6 @@
 import time
 import types
+import cherrypy
 from threading import Thread
 from StringIO import StringIO
 from Test_controller import Test_controller
@@ -817,7 +818,150 @@ class Test_files( Test_controller ):
     assert u"access" in result[ u"error" ]
 
   def test_purge_unused( self ):
-    raise NotImplementedError()
+    self.login()
+
+    self.http_upload(
+      "/files/upload?file_id=%s" % self.file_id,
+      dict(
+        notebook_id = self.notebook.object_id,
+        note_id = self.note.object_id,
+      ),
+      filename = self.filename,
+      file_data = self.file_data,
+      content_type = self.content_type,
+      session_id = self.session_id,
+    )
+
+    # the file is not linked to from the note's contents, so this should delete it
+    cherrypy.root.files.purge_unused( self.note )
+
+    db_file = self.database.load( File, self.file_id )
+    assert db_file is None
+    assert not Upload_file.exists( self.file_id )
+
+  def test_purge_unused_empty_link( self ):
+    self.login()
+
+    self.http_upload(
+      "/files/upload?file_id=%s" % self.file_id,
+      dict(
+        notebook_id = self.notebook.object_id,
+        note_id = self.note.object_id,
+      ),
+      filename = self.filename,
+      file_data = self.file_data,
+      content_type = self.content_type,
+      session_id = self.session_id,
+    )
+
+    self.note.contents = '<a href="/files/download?file_id=%s"></a>' % self.file_id
+    self.database.save( self.note )
+
+    # the file is linked to from the note's contents but the link title is empty, so this should
+    # delete it
+    cherrypy.root.files.purge_unused( self.note )
+
+    db_file = self.database.load( File, self.file_id )
+    assert db_file is None
+    assert not Upload_file.exists( self.file_id )
+
+  def test_purge_unused_keep_file( self ):
+    self.login()
+
+    self.http_upload(
+      "/files/upload?file_id=%s" % self.file_id,
+      dict(
+        notebook_id = self.notebook.object_id,
+        note_id = self.note.object_id,
+      ),
+      filename = self.filename,
+      file_data = self.file_data,
+      content_type = self.content_type,
+      session_id = self.session_id,
+    )
+
+    self.note.contents = '<a href="/files/download?file_id=%s">file link</a>' % self.file_id
+    self.database.save( self.note )
+
+    # the file is linked to from the note's contents, so this should not delete it
+    cherrypy.root.files.purge_unused( self.note )
+
+    db_file = self.database.load( File, self.file_id )
+    assert db_file
+    assert db_file.object_id == self.file_id
+    assert db_file.filename == self.filename
+    assert Upload_file.exists( self.file_id )
+
+  def test_purge_unused_all_links( self ):
+    self.login()
+
+    self.http_upload(
+      "/files/upload?file_id=%s" % self.file_id,
+      dict(
+        notebook_id = self.notebook.object_id,
+        note_id = self.note.object_id,
+      ),
+      filename = self.filename,
+      file_data = self.file_data,
+      content_type = self.content_type,
+      session_id = self.session_id,
+    )
+
+    self.note.contents = '<a href="/files/download?file_id=%s">file link</a>' % self.file_id
+    self.database.save( self.note )
+
+    # the file is linked to from the note's contents, but because of the purge_all_links flag, it
+    # should be deleted anyway
+    cherrypy.root.files.purge_unused( self.note, purge_all_links = True )
+
+    db_file = self.database.load( File, self.file_id )
+    assert db_file is None
+    assert not Upload_file.exists( self.file_id )
+
+  def test_purge_unused_multiple_files( self ):
+    self.login()
+
+    self.http_upload(
+      "/files/upload?file_id=%s" % self.file_id,
+      dict(
+        notebook_id = self.notebook.object_id,
+        note_id = self.note.object_id,
+      ),
+      filename = self.filename,
+      file_data = self.file_data,
+      content_type = self.content_type,
+      session_id = self.session_id,
+    )
+
+    self.note.contents = '<a href="/files/download?file_id=%s">file link</a>' % self.file_id
+    self.database.save( self.note )
+
+    other_file_id = u"23"
+    self.http_upload(
+      "/files/upload?file_id=%s" % other_file_id,
+      dict(
+        notebook_id = self.notebook.object_id,
+        note_id = self.note.object_id,
+      ),
+      filename = u"otherfile.png",
+      file_data = u"whee",
+      content_type = self.content_type,
+      session_id = self.session_id,
+    )
+
+    # one file is linked from the note's contents but the other is not. the file that is not linked
+    # should be deleted
+    cherrypy.root.files.purge_unused( self.note )
+
+    db_file = self.database.load( File, self.file_id )
+    assert db_file
+    assert db_file.object_id == self.file_id
+    assert db_file.filename == self.filename
+    assert Upload_file.exists( self.file_id )
+
+    other_db_file = self.database.load( File, other_file_id )
+    assert other_db_file is None
+    assert not Upload_file.exists( other_file_id )
 
   def login( self ):
     result = self.http_post( "/users/login", dict(