Abstract
This two-part review of support groups and group therapies provides a perspective on the continuum of groups for patients with cancer: from open-ended, drop-in groups that provide supportive, educational, or self-help group experiences to time-limited or closed groups such as supportive-expressive group therapy based on the principles of existentialism. Part I reviews the history and theoretical background of support groups and group therapies and explores the breakthroughs in mental health research showing how these groups enhance patients' quality of life. Part II will address issues regarding group process, group organization and leadership,and the curative aspects of groups for patients.