Proactive disability management practices among employers have been associated with reduced frequency and duration of disability. Supervisors have a critical role in disability prevention. However, few studies have evaluated training efforts to modify supervisor responses in order to improve disability outcomes. In this study, 108 supervisors representing seven employers were provided a 1.5-h training session to reinforce a proactive and supportive response to work-related musculoskeletal symptoms and injuries among employees. Pre- and post training results showed improvements in supervisor confidence to investigate and modify job factors contributing to injury, to get medical advice, and to answer employees' questions related to injury and treatment (p < .05). More supervisors reported decreases (38.5%) than increases (9.6%) in lost work time within their departments. These data provide evidence that this approach may improve disability outcomes of work-related musculoskeletal disorders. Controlled trials with disability outcome data are needed to confirm these results.