Prophylactic mastectomy continues to be a controversial procedure as a preventive tool against breast cancer. Recent research and other scientific advances, however, have refocused attention on better risk estimation, evidence of efficacy, and improvements in reconstruction. The recently discovered genetic markers BRCA1 and BRCA2 have become increasingly important in determining risk; a BRCA1-positive patient's risk of developing breast cancer by the age of 65 is estimated at 50 percent to 80 percent. BRCA1- and BRCA2-positive breast cancers also tend to be higher grade and occur in younger women (making mammography less effective). Genetically linked breast cancers are usually estrogen receptor negative, making them less susceptible to chemoprevention. Various predictive models and recommendations by experts in the field are also available for today's clinicians to ascertain who should be genetically tested. The benefit of bilateral prophylactic mastectomy, although difficult to estimate, can be evaluated by looking at the incidence of breast cancer in studies of patients who have previously undergone prophylactic mastectomy. The estimated risk reduction from these studies is 80 percent to 95 percent. Similarly, life expectancy is believed to be increased from 2.9 to 5.3 years. The psychological benefits include a 70 percent rate of satisfaction and a decrease in emotional concern over developing breast cancer by 74 percent of women who underwent prophylactic mastectomy. Although reconstruction results may vary, most patients have been very satisfied and some may achieve cosmetic results that are better than their preoperative situation. Patient selection for specific types of reconstruction after prophylactic mastectomy and the decision to proceed should be based on surgical risk and the likelihood of a good outcome. The choice of mastectomy incision should consider the size of the breast, preexisting scars, patient risk factors, and the planned method and goal of reconstruction. The authors propose certain guidelines based on degree of ptosis and cup size when planning prophylactic mastectomies with reconstruction. In certain cases, a nipple-sparing mastectomy may provide cosmetic advantages that could outweigh the additional oncologic risk.