The relationship between cosmetic and functional results of breast conserving therapy and psychosocial functioning was examined in a sample of 76 patients with early stage breast cancer, who received treatment between 1975 and 1985. The patients were interviewed at their homes regarding breast cosmesis, arm functioning and psychosocial health, and subsequently attended the hospital for independent assessment of cosmetic and functional outcomes by clinical observers. High levels of psychological distress, disturbance of body image, and decreased sexual functioning were noted in approximately one-quarter of the study sample. About half of the patients expressed heightened concern with disease recurrence and their future health. Psychosocial problems were only modestly associated with treatment-related cosmetic and functional outcomes, as determined by clinical ratings and objective assessments. The patients' own ratings of breast cosmesis and arm functioning exhibited somewhat higher correlations with self-reported psychosocial functioning. In particular, a significant association was noted between the patients' ratings of overall cosmesis and arm edema and their body image (r = 0.48 and r = 0.43, respectively). The association between cosmetic and functional results and self-reported psychosocial health was strongest among those patients younger in age and treated longer ago. These findings suggest that, in order to evaluate the impact of breast conserving therapy on the patients' quality of life, the patients' own assessments of cosmetic and functional outcomes should be used as a primary source of information.