This book completes my Donald Norman trifecta. Reading all three (including The Design of Everyday Things and Emotional Design) at once provided an interesting perspective on the evolution of Norman’s thinking. I actually think this was his best book, despite several Amazon reviews that suggested it was his worst. Here he steps back from individual objects and looks at whole systems (including service systems like hotels and airports). He also considers the nature of complexity itself, where it comes from, and how we can cope with it.