diff --git a/backup.py b/backup.py
index 846e107..0a49a53 100755
--- a/backup.py
+++ b/backup.py
@@ -15,7 +15,7 @@ class BackupError(Exception):
 class Backup(object):
 
     RSYNC = os.environ.get('RSYNC', 'rsync')
-    RSYNC_DEFAULT_ARGS = ['-aO', '--partial']
+    RSYNC_DEFAULT_ARGS = ['-aO', '--partial', '--delete']
     RSYNC_EXTRA_ARGS = shlex.split(os.environ.get('RSYNC_EXTRA_ARGS', ''))
 
     log = logging.getLogger('backup')