With the growing recognition of the importance of systematic and evidence-based approaches to mental health policy development, there is an increased need for public policy advocacy training for psychology trainees and psychologists. These individuals possess clinical, research, and interpersonal expertise, and are capable of informing policymakers as to how psychologically informed legislation can better serve society. Lack of awareness of advocacy issues is a prominent barrier to advocacy involvement. Advocacy training may help to overcome such barriers by increasing motivation for involvement, the feeling of competence regarding impact on policies, and, most importantly, knowledge of current issues. The purpose of the present study was to provide an assessment of the relationship between training in public policy advocacy and the frequency of engagement in advocacy-related activities. The sample included 79 graduate trainees and professionals in the field of psychology. There was a significant, positive, linear relationship between reported hours spent in advocacy training and hours of advocacy involvement. Additionally, the rate at which involvement hours increased as a function of training hours was more than double for practicing professionals compared with students. Implications include an increased need for advocacy training both early in graduate education as well as throughout the professional practice of psychology.