Kingsley Davis (1908-1997) was one of the pioneers in social demography, and was particularly identified with the theory of the demographic transition. This holds that the process of industrialization first causes mortality to decline, leading to a substantial rate of population growth and only later causes fertility to fall, leading eventually to the cessation of population growth. Kingsley Davis is especially remembered for his arresting and forceful critique of family-planning programs intended to achieve zero population growth. Before he devoted his major attention to social demography, Davis had distinguished himself through influential articles on the structure of family and kinship, including the topics of jealousy and sexual property, the sociology of prostitution, and illegitimacy. He had an early interest in structural-functional analysis, which resulted in his famous and controversial article on stratification, co-authored with Wilbert Moore, and his equally famous presidential address to the American Sociological Association in 1959. David Heer's biography of Kingsley Davis is based on material contained in the Kingsley Davis Archive at the Hoover Institution Library at Stanford University, the Kingsley Davis graduate file at Harvard University, the interview of Kingsley Davis by Jean van der Tak in Demographic Destinies (1990), and David Heer's personal relationship with Kingsley Davis. The book also contains thirty of the most important writings by Kingsley Davis. These were chosen, in part, for the number of citations received in the Cumulative Social Science Citation Index, and in part to ensure that readers would be able to assess the continuity of Kingsley Davis's ideas at all stages of his career.