One hundred crossbred beef steers were used in two experiments to evaluate effects of growth implants on performance. Steers were implanted either at 3.5 months and weaning (CALF); at weaning (WEAN); or not implanted (NONE). In Experiment 1 implanted steers weighed more at weaning (P = 0.01), and had a higher ADG for the entire trial compared to non-implanted steers (P = 0.03). In Experiment 2, at 80 d post wean, implanted steers outweighed NONE (P = 0.09). Overall ADG (P = 0.01) was greater for cattle that were implanted. In the feedlot the CALF group had the lowest ADG (P = 0.01), and final BW (P = 0.07). At harvest CALF had the highest dressing percentage (P = 0.04), smallest LMA (P = 0.1), and lowest IMF (P = 0.06). Implants can increase productivity in beef cattle however, marketing and management strategy will dictate use.