Patients attending weight reduction clinics were tested at the beginning of the program to assess a variety of background variables which might influence successful weight loss. These included measures of self-esteem, social acceptance, locus of control, responsiveness to external stimuli, attitudes toward weight loss, and knowledge about nutrition. Success was related to social conformity and desire for social acceptance but not to self esteem or locus of control. Individuals who believed that poor eating habits caused their obesity and those who were less responsive to environmental cues which may trigger feeding, were also more successful.