Like most books about the future, this one is mainly about the past. The author, editor of The Economist for the past decade, has an easy, informal, gently ironic style, is good at asking questions, and provides at least hints of the answers. He notes the remarkable progress of much of the globe since World War II and asks whether it can be continued for another 25, 50, or even 100 years. His explanation for the success is twofold: U.S. leadership in the world and the vitality of capitalism as a mechanism for organizing production. The book sketches possible future challenges to both: European envy, Japanese vulnerability, Chinese ambition, and widespread political turbulence in the first case; economic instability, inequality, and environmental degradation in the second. The author concludes on a note of paranoid optimism -- that the challenges will be serious and will require skillful management, but that they will not in the end be devastating to continuing economic and political progress. The book offers cautious optimism about the outlook for the twenty-first century. Above all, it exudes common sense.