Involvement in the public policy process is essential to the continued growth of the profession of psychology. The authors posit that five dimensions of involvement in the policy process are fundamental to ensuring the success of advocacy efforts: patience, persistence, the establishment of effective partnerships, emphasizing interpersonal relationships in the policy process, and the adoption of a long-term perspective. These key mediators are described in the context of current major public policy issues affecting psychology: mental health legislation in general, prescriptive authority, provision of psychological services in community health centers, expansion of the available treatments for autistic spectrum disorders, and recasting psychology as a primary health-care delivery profession. The authors suggest that policy makers will value the contributions of psychology only insofar as they are convinced of the profession’s ability to improve the public weal.