2008/7/23 Shadowfirebird <shadowfirebird / gmail.com>: > The annoying thing is that my actual code worked "fine" when it was > all in one file but stopped working when I split the objects into > different files. If you write everything in one file, it only works if you define class Two before class One. If you reverse the definitions, you get the same error. In Ruby you have to define a constant before you can use it. This is independent of require. If you create a file main.rb with require "test1" require "test2" the code is working. If you reverse those two lines, you get the error. This is the same behavior as in the one-file example. I suggest you add some debugging statements in your code to understand the sequence when loading files, for example in file test1.rb: puts "start test1" require "test2" puts "before test1.One" class One < Two puts "in test1.One" def self.testone(); Two.whoistwo; end def self.whoisone(); puts "class one"; end end puts "end test1" or something like this. Regards, Pit