64 women with operable breast cancer were randomly allocated at the time of mastectomy to a group receiving immediate breast reconstruction or to a control group to whom breast reconstruction was offered 12 months later. The objective of the trial was to determine whether immediate breast reconstruction affected the psychosocial morbidity of mastectomy. Immediate reconstruction reduced the psychiatric morbidity assessed 3 months after operation, predominantly in women with unsatisfactory marriages. Women who underwent reconstruction had more freedom of dress and were less likely to be repulsed by their own naked appearance than women who did not undergo reconstruction. Sexual and social morbidity were not affected.