Tony Smith is right in judging that the time is ripe for reexamination of the concept of imperialism in the light of historical and contemporary fact rather than outworn theory or mythology. Inevitably he has to devote much space to the problems of definition, but he has enough left over to describe with rare objectivity Britain's nineteenth-century experience and that of America in the twentieth, up to the beginning of the decline of American global power in the 1970s. A thoughtful, well-reasoned book.