The Handbook of Developmental Science, Behavior, and Genetics brings together the cutting-edge theory, research and methodology that contribute to our current scientific understanding of the role of genetics in the developmental system. It commemorates the historically important contributions made by Gilbert Gottlieb in comparative psychology and developmental science. It includes an international group of contributors who are among the most respected behavioral and biological scientists working today. It examines the scientific basis for rejecting the reductionism and counterfactual approach to understanding the links between genes, behavior, and development. It documents the current status of comparative psychology and developmental science and provides the foundation for future scientific progress in the field.