Why some cities prosper and others decay is the question posed by the author of the controversial The Death and Life of Great American Cities. Searching history, she finds that the city from the beginning has been the place where new kinds of work have developed from old; and that prosperous urban economies have been those which maximized opportunities for creativity. With splendid success, Mrs. Jacobs contrasts the stagnation and obsolescence of cities dominated by one or two vast industries (Manchester, England; Rochester, New York) with the continuing growth of cities (e.g. Detroit circa 1900) where an economy of small varied producers served as a basis for the articulation of offshoot enterprises. The author makes an excellent case, as in her earlier book, for the wisdom of encouraging smallness, variety, and experiment in our cities. For her, even the diseases of urban life (air pollution, garbage) have potential for stimulating fresh invention, wealth, and growth. Generally clear and well-argued, the book's only flaw is in its lengthy opening speculations on the origins of cities. Contrary to most thinkers, who hold that cities grew up on an agricultural base, this ardent partisan of urban life insists that healthy rural economies sprang from the cities. The point is important in its implications for the underdeveloped world, but the substantiating evidence is largely conjectural and the presentation taxing. Readers who slog through it will be amply rewarded by a provocative work which should challenge all who care about the future of our cities.