Welcome to the Encyclopedia of Couple and Family Therapy, an evolving comprehensive reference work.With strong leadership, our renowned editorsin- chief, Jay Lebow, Anthony Chambers, and Doug Breunlin, who are both family therapists and family scholars, and over 20 associate editors have recruited an impressive array of talented contributors to create a truly encyclopedic compilation of entries. Couple and family therapy is a vital area within the broader field of mental health treatment. With relational science and systemic concepts at its foundation, the field of couple and family therapy includes an array of empirically derived methods for approaching couples and families that effectively treat a wide variety of common problem areas. The past decade has witnessed a tremendous surge in the practice of couple and family therapy as well as interest in this endeavor, accompanied by an explosion of relevant research and important advances in treatment. Given the multifaceted nature of couple and family therapy, this online and print reference work seeks to provide readers with easily accessible, high-quality, research-based information across multiple disciplines. Because the field of couple and family therapy has been in existence for over 70 years, many of its original ideas are lost in books and chapters that are out of print. Furthermore, given the array of varying approaches in what is a pluralistic multidisciplinary field, writings are published in diverse places and within parallel literatures. Scholars and students alike, therefore, are often challenged to locate concise sources for core information in this body of work. Conscious of the field’s rich history, the encyclopedia includes entries that cover both early seminal contributions (including homeostasis, marital schism, second-order cybernetics) and more recent developments.