The author reviews 6 years of experience and 416 patients in whom polyurethane implants were used for augmentation and reconstruction of the breast. As with many other plastic surgeons, early use was confined to "salvage cases." Owing to the impressive results, use was extended to routine augmentation. Polyurethane implants are now used exclusively for aesthetic breast surgery. Results are evaluated for replacement of gel capsules and simple and radical mastectomy reconstruction. Gel capsules (Baker stages III to IV), in which prostheses were removed and replaced with polyurethane-covered implants, improved in 29 of 32 patients (87 percent). For reconstruction, placement of polyurethane implants in unscarred situations gives far superior results than following repeated procedures. The incidence of infection is no higher than with gel implants. Removal without capsulectomy was not a problem in most instances. However, on two recent occasions capsulectomy was extremely difficult.