A series of four experiments were conducted to determine the effect of stilbestrol implantation, when followed by feeding of stilbestrol, on steer performance and carcass characteristics. A total of 275 steers were used in this study one-half of which were implanted with 12 or 24 nig. of stilbestrol at the start of the pasture season. At two sub-stations a 12 mg. implant was used and at two other substations a 24 mg. implant was used. Implanting with 12 and 24 mg. increased rate of gain on pasture by 17.8% and 14.9% respectively. The oral feeding of 10 mg. of stilbestrol daily per steer increased gains by 14.4% and 13.6% for the non-implanted and 12 mg. implanted steers, respectively. The daily gains were similar for the control and implanted steers. Feed required per 100 lb. of gain was decreased by the feeding of stilbestrol. The oral feeding of stilbestrol increased gains by 11.2% and 7.9% for the non-implanted and the 24 mg. implanted steers, respectively. The steers previously implanted with 24 mg. of stilbestrol gained slightly slower than the non-implanted steers. Feed required per 100 lb. of gain was decreased by the feeding of stilbestrol. There was little difference in carcass grade scores, dressing percent, area of longissimus dorsi or fat covering over the 12th rib between implanted and non-implanted steers or between control and steers fed stilbestrol. The combination of an implant and oral feeding of stilbestrol did not appear to influence carcass characteristics.