Review of Birth quake: The baby boom and its aftershocks, by Diane J. Macunovich: The multiplicity of impacts emanating from a generation being smaller or larger than its parents' generation has concerned demographers since the 1970s when the issue was the focus of work by Richard Easterlin. The baby boom -- the substantial rise and then fall in birth rates in many industrialized countries during the 1940s to 1960s - has given rise to much interesting debate on its causes and consequences. For example, a considerable amount of literature now exists on the likely social and economic impacts of the baby boom generation moving into the retirement ages over the first quarter of this century (in areas such as pensions and healthcare costs, the "grey" vote, changes in demand for products, and so on). Diane Macunovich has played an important role in the investigation of the baby boomers and cohort size fluctuations in general over the last decade. Synthesising previous work by the author, this book focuses on "how so much of the social and economic change over the last 50 years has been related to the post-WWII baby boom and that generation's passage through the life cycle" (p. 2). The principal focus of the book is the United States. As the author notes in chapter 5, early studies on cohort effects placed quite a lot of importance on relative cohort size. These studies concluded that the crowding of the labour market by the large baby boom cohorts resulted in lower wages relative to smaller cohorts because younger workers are not perfect substitutes for older workers with more skills and experience.