Ostracism is among the most powerful means of social influence. From schoolroom time-outs or the “silent treatment” from a family member or friend, to governmental acts of banishment or exile, ostracism is practiced in many contexts, by individuals and groups. This lucidly written book provides a comprehensive examination of this pervasive phenomenon, exploring the short- and long-term consequences for targets as well as the functions served for those who exclude or ignore. Within a cogent theoretical framework, an exemplary research program is presented that makes use of such diverse methods as laboratory experiments, surveys, narrative accounts, interviews, Internet-based research, brief role-plays, and week-long simulations. The resulting data shed new light on how ostracism affects the individual's coping responses, self-esteem, and sense of belonging and control. Informative and timely, this book will be received with interest by researchers, practitioners, and students in a wide range of psychological disciplines.