Hi! I'm not at all new to programming, I know OO-concepts but I don't have any hands-on experience with designing/programming OO except for small tests. I'm also a Ruby newbie, but have been coding a LOT of C, (advanced) Shellscripts and Python. I need advice on good design, taking features of Ruby into consideration. I want a tree of objects like this: a1 b1 c1 b2 c1 c2 d1 and so on... The a#-objects will hold default values and methods for b# and b# will hold default values for c# and so on. When a value in a# is changed I want its children to immediatly inherit them also, if they aren't overridden. b# will be subclasses of a#, c# will be subclasses of b# etc. I have to be able to dynamically (at runtime) add and delete children. What is a good way to design this with the OO-features of Ruby, keeping it as readable and clean as possible? Regards, Per Wigren