Organizational psychology is the science of psychology applied to work and organizations. It is a field of inquiry that spans more than a century and covers an increasingly diverse range of topics as the nature of work continues to evolve. This publication provides a comprehensive treatment of key topics that capture the broad sweep of organizational psychology. It features contributions by sixty-nine leading scholars who provide cutting-edge reviews, conceptual integration, and directions for future research. The forty-two articles of the handbook are organized into ten major sections, spanning two volumes, including such topics imperative to the field as: the core processes of work motivation, job attitudes and affect, and performance that underlie behavior at work; phenomena which assimilate, shape, and develop employees (i.e. socialization, networks, and leadership); the challenges of managing differences within and across organizations, covering the topics of diversity, discrimination, and cross-cultural psychology; and the powerful influence of technology on the nature of work and work processes. This two-volume set compiles knowledge in organizational psychology to date, and looks ahead with a roadmap for the future of the field.