Breast surgery is a common procedure performed in women. Many women who undergo breast surgery suffer from ill-defined pain syndromes. Although there exists a few reports on the incidence of post mastectomy pain, there are no published reports on chronic pain after breast reconstruction. This investigation attempts to characterize the pain after four types of breast surgery: (1) mastectomy, (2) mastectomy with reconstruction, (3) cosmetic augmentation, and (4) breast reduction. A questionnaire was mailed to 479 women who underwent breast surgery at the University of California, San Diego Medical Center between January 1988 and December 1992. A second mailing was sent to women who did not respond to the first mailing. Women were divided into four groups; mastectomy, mastectomy with reconstruction, cosmetic augmentation, and breast reduction. In the mastectomy and mastectomy with reconstruction groups, only women who had a lumpectomy with axillary dissection, a modified radical mastectomy, or a radical mastectomy were used in the study. 59% of the women responded. The incidence of pain occurring at least one year after surgery in the mastectomy + reconstruction group (49%) was significantly higher than the mastectomy (31%) and breast reduction (22%) groups. Thirty-eight percent of the women with breast augmentation complained of pain. Women who had reconstruction using breast implants had a higher incidence of pain (53%) than those without (30%). The pain incidence in women who had reconstruction without implants was identical to women who had a mastectomy without reconstruction. There was no relationship between the use of silicone or saline implants and pain (22% and 33% respectively). However, the submuscular placement of the implants resulted in a significantly higher incidence of pain (50%) than the subglandular placement (21%). Of the women that reported pain, arm pain was significantly higher in the mastectomy and mastectomy + reconstruction group (56% and 42%, respectively) as compared to the breast reduction group (0%). Most patients reported intermittent pain in all groups. Of the women that reported pain, the mastectomy and mastectomy + reconstruction group had higher pain related to movement (41% and 42%, respectively) than the augmentation and breast reduction groups (15% and 9%, respectively). The peak pain intensity was significantly higher in the augmentation group as compared to the mastectomy group. Our incidence of post mastectomy pain is higher than most reports. The incidence of breast pain is highest in the mastectomy + reconstruction and augmentation groups which is assumed to be secondary to breast implants. Every effort should be made to achieve the best cosmetic result in breast reconstruction which in many cases justifies the use of breast implants. However, these women should be counseled on the possibility of developing chronic pain.