The goal of this new Handbook of Closeness and Intimacy is to bring together the latest thinking on the scientific study of closeness and intimacy from the most active and widely recognized relationship scholars in social and clinical psychology, communication studies, and related disciplines. The chapters address six general questions: What are closeness and intimacy? How can they be measured? What are the general processes? What individual differences play a role in closeness and intimacy? What situational factors play a role? Is there a dark side to closeness and intimacy? Each chapter in the Handbook of Closeness and Intimacy follows a similar format so as to provide continuity for the reader. Each contributing author: defines their understanding of the meaning of closeness and intimacy; summarizes an existing program of research and provides a clear overview of a particular theoretical framework; presents a plethora of new ideas, applications, and previously unstated theoretical connections; and provides applicable cross-references to other chapters to further integrate the material presented. What stands out in this volume is its specific focus on the pivotal phenomena of clo