'This elegant and enjoyable book describes the theory of imperfect competition in an explicitly general-equilibrium framework. . . The main strength of the book is that it provides a coherent and precise narrative of developments in two theoretical areas to which the author has made important contributions. . . The writing has an elegiac quality. The author contrasts the "Golden Sixties", when "general equilibrium theory was superbly flourishing" with the present, "much darker period for this field of microeconomic theory". The elegant and deep results described here will give the reader a sense of the mood of the period as well as the intellectual accomplishments.'