The first chapter of the GOF book is worth reading for any OO practioners. Especially the discussion on favoring composition over inheritance. Functional programmers have been using composition since day 1. It seems like the OO movement has been trying to work functional programming back in. Design Patterns is a perfect example. Many of the patterns involve classes with only methods (such as the Strategy pattern). This goes against basic OO which defines a class as encapsulated data and the methods that operate on this data. OO teams would be wise to investigate GOF and some newer literature on OO to expand the teams vision beyond the limited capabilities of Novice level OO.
in reply to Are design patterns worth it?