This book examines the basic mechanisms behind the modernization of demographic behaviour. The author has marshalled an impressive amount of statistical material relating to 67 countries, half of them less developed, and covering the period 1720-1984. The whole sweep of western demographic experience is dealt with comprehensively and impartially, and though technically sophisticated, the book also covers issues of interpretation and analysis. The author shows how mortality decrease necessarily precedes fertility decline and how so-calledexceptions are simply false exceptions; how the decline of fertility is dependent on important and manifold social transformations; and reveals the strong connections between international migration and the course of demographic transition. Chesnais demonstrates that less developed countries arefollowing the same general patterns as MDCs and argues that the theory of demographic transition must include the effect of population changes on the economic progress of society.