OBJECTIVE: To examine the physical function, gait, and quality of life of patients after total hip replacement (THR) randomly assigned to either a targeted home- or center-based exercise program. DESIGN: Randomized controlled trial. SETTING: Rehabilitation research center in Australia. PARTICIPANTS: Twenty-three patients with unilateral THR were randomly assigned to a supervised center-based exercise group (n=11) or an unsupervised home-based exercise group (n=12). INTERVENTION: The center-based group completed an 8-week targeted exercise program while under the direct supervision of a physiotherapist. After initial instruction, the home-based group completed the 8-week targeted exercise program at home without further supervision. MAIN OUTCOME MEASURES: Quality of life, physical function, and spatiotemporal measures of gait. RESULTS: No significant interaction (group by time) or main effects of grouping were found. Within each group, quality of life, and stair climbing improved significantly (P<.05) as did Timed Up & Go test and 6-minute walk test performances (P<.05). Walking speed increased by 16 cm/s (P<.01), cadence by 8 steps/min (P<.05), step length by 4.7 cm (P<.05), and double-support time reduced by a factor of 16%. Step length symmetry showed significant improvement (P<.05) over time. Step length differential between the affected and unaffected limbs reduced from 4.0 to 2.7 cm. CONCLUSIONS: The targeted strengthening program was effective for both the home- and center-based groups. No group differences were found in the majority of the outcome measures. This finding is important because it shows that THR patients can achieve significant improvements through a targeted strengthening program delivered at a center or at home.