Here are some pages that talk about how to use patterns (or not) in developing software.
PatternsMisconceptions PatternsAreNotClipArt SomePatternsQuestionsAnswered ExtremePatternsUser ExtremeProgrammingAndPatterns ImplementingPatterns LetPatternsEmerge RefactoringToPatterns TestDrivenDesignAndPatterns FormalMethodsAndPatterns LittleRulesAndPatterns PatternsForBeginners ProgrammingWithPatterns PurposeOfPatterns SuccessesAndPatterns DesignPatternsConsideredHarmful (merge candidate) PatternsConsideredHarmful PatternSkepticism PatternsAreDead[They're arranged roughly by similarity; I plan to come back and add some gloss, but right now, I'm too tired, having spent a couple of hours picking these ones out.--GeorgePaci]