Schrage examines the approaches to successful prototyping at companies such as AT&T, Boeing, Microsoft, and DaimlerChrysler and describes the kind of culture that's needed for encouraging innovation. In the last chapter, he lays out the 10 rules of serious play, including: Be willing to fail early and often; know when the costs outweigh the benefits; know who wins and who loses from an innovation; build a prototype that engages customers, vendors, and colleagues; create markets around prototypes; and simulate the customer experience. Well-written and inspiring, Serious Play, is a first-rate user's guide for managers, project leaders, and other innovators. --Dan Ring