Given the current changes in health care, being able to obtain and use research evidence that supports occupational therapy treatment has become increasingly important. The purpose of this study was to synthesize available evidence on the effectiveness of occupational therapy–related treatments for persons with Parkinson’s disease. A meta-analysis was performed to achieve this synthesis. The results revealed small to moderate positive effects of intervention on outcomes related to clients’ capacities and abilities as well as for outcomes related to function during activities and tasks. Limitations in the research reviewed for this meta-analysis may have resulted in an underestimation of treatment effects. Occupational therapists can use results from this meta-analysis to communicate with clients about the possible benefits of participating in occupational therapy.