Great Reading: Patterns

I'm reading a book that software executives can use to understand Design Patterns. After going through this book you'll be able to ask better questions about the architecture of your OO software. So far I've only gone through the Strategy, Observer, and Decorator patterns... but suddenly I understand them and can talk at a much higher level of design than ever before. The book is well written and engaging, it is called:

Head First Design Patterns

by Eric and Elizabeth Freeman. The style is credited to Kathy Sierra and Bert Bates, creators of the Head First series. Good stuff.