diff --git a/lib/X11/display.rb b/lib/X11/display.rb
index af826cd..d8bd558 100644
--- a/lib/X11/display.rb
+++ b/lib/X11/display.rb
@@ -1,8 +1,8 @@
 module X11
 
   class DisplayError < X11Error; end
-  class ConnectionError < DisplayError; end
-  class AuthorizationError < ConnectionError; end
+  class ConnectionError < X11Error; end
+  class AuthorizationError < X11Error; end
 
   class Display