The Working Alliance, consisting of building bonds, establishing goals, and developing tasks, has been deemed the cornerstone of helping professions, and has been found to significantly and reliably predict client outcomes. The importance of client characteristics and perceptions of working alliance has been established in the literature. Less is known about service provider qualities that impact the working alliance. This study utilized 104 rehabilitation service providers to assess the impact of education, work experience, and disability category on working alliance efficacy. Results indicate that rehabilitation service providers with more education had significantly higher working alliance efficacy pertaining to clients with physical disability. This suggests that master level rehabilitation service providers have greater confidence to build bonds, identify goals, and structure tasks when working with clients with physical disabilities. No differences were found between education groups on working alliance efficacy for psychiatric disability. Work experience was found to relate to working alliance efficacy for physical disability, not psychiatric disability. The results of this study provide initial support for the notion that rehabilitation service providers with more education and more work experience demonstrate a more effective working alliance in their efforts with clients who have physical disabilities. The non significant differences in psychiatric disability working alliance scores among service providers with varying education levels and work experience may be indicative of provider stigma or burnout when working with this population. (Contains 3 tables.)