This book results from a symposium sponsored by the Program for Dialogue on Science, Ethics, and Religion (DoSER) of the American Association for the Advancement of Science (AAAS). The organizers of the symposium are the editors of this volume. Contributors focus on the current status of research on sociality and the evolution of behavior in nonhuman and human primates. Against the tendency of sociobiologists to emphasize the selfishness of the gene pool, the authors examine questions related to the evolution, cultural viability, and hormonal underpinnings of human sociality, and describe patterns of sociality among nonhuman primates for the light these may shed light on human social behavior.