The book that you hold in your hands is the second in a series. The two titles in the series are the following: Genetic Influences on Human Fertility and Sexuality: Theoretical and Empirical Contributions from the Biological and Behavior Sciences Edited by Joseph Lee Rodgers, David C. Rowe, & Warren B. Miller Published by Kluwer Academic Press, 2000 The Biodemography of Human Reproduction and Fertility Edited by Joseph Lee Rodgers & Hans-Peter Kohler Published by Kluwer Academic Press, 2002 The series has published chapters by researchers who study human fertility, from a particular perspective: Biodemography. We welcome your interest and participation in this developing subfield. Or, perhaps, biodemography may be better referred to as a "superfield. " Because biodemography so naturally crosses interdisciplinary boundaries, and because its application draws together researchers from disparate disciplines, it may well be more appropriate to consider that biodemography subsumes a number of other disciplines, rather than the other way around. In this preface, we will describe our own efforts and those of many others to promote and develop the study of human fertility, using methods, models, and theories from both biological and demographic domains. In December, 1997, 25 participants from three different countries gathered in Tucson, Arizona for a small conference with the title "Genetic Influences on Fertility-Related Processes. " That conference represented a fascinating blending of research from two apparently separate domains.