Some early psychoanalysts, especially Alfred Adler, a student of Sigmund Freud, believed that many individual problems were social in origin. In the 1930s Adler encouraged his patients to meet in groups to provide mutual support. At around the same time, social work groups began forming in mental hospitals, child guidance clinics, prisons, and public assistance agencies. A contemporary descendant of these groups is today's support group, in which people with a common problem come together, without a leader or therapist, to help each other solve a common problem. Groups such as Alcoholics Anonymous, Narcotics Anonymous, and