A biological understanding of social behavior is now part of modern science. We know that previously assumed social or cultural causes of behavior have their origins, at least in part, in human biology. Similarly, we now know that social circumstances (such as stressful working conditions) can have profound effects on our biological functioning. The purpose of this book is to introduce scholars to biological and evolutionary perspectives on organizational behavior (OB). Its specific goals are to: (1) start a dialogue between OB and biology, (2) encourage research on biological and OB linkages, (3) provide an initial framework for biological bases of organizational behavior, and (4) stimulate discussions about potential applications. Conceptually, the chapters on this volume reflect an “extended phenotype” view of human behavior in organizations—examining the interplay and inter-relations among genotypes, phenotypes, and symbolic and tangible human creations. The volume contains 12 chapters, which are organized into five sections: introduction; genetics; individual differences and work behavior; physiology and organizational behavior; evolution and organization; and challenges ahead. The chapters contain enough background to orient readers who may have little knowledge of biology, yet they also provide substantive contributions to advancing understanding of specific areas of biology and human behavior in organizations. They are both synthetic and forward looking.