The purpose of this study was to evaluate the effects of an intervention on pharmacists' behaviors, knowledge, and attitudes related to skin cancer prevention counseling. Fifty-four pharmacy sites (N = 178 pharmacists) were randomly assigned to the intervention or control condition. Intervention consisted of video-based training, prompts installed in the pharmacy to promote pharmacist-patient discussions on the topic, and group-based feedback on previous week's counseling rates. Outcomes were measured using a mailed survey. The proportion of patients counseled at post-test was significantly higher among intervention subjects, adjusting for pretest values. Similar results were found for pharmacists' skin cancer knowledge and self-rated expertise, but not for counseling-related attitudes. The intervention was successful. If implemented on a wide scale, large segments of the U.S. population would be exposed to skin cancer prevention advice.