Radio and television offer promising media for addressing large-scale social problems. Unfortunately, very few mass-media messages have utilized social psychological theories of persuasion and influence. This article summarizes 2 studies that evaluated the effectiveness of a state-sponsored public service announcement aimed at reducing improper disposal of used motor oil among do-it-yourself oil changers. Study 1 was a field experiment with 120 oil changers in San Diego County. Inertial resistance and low perceived behavioral control were identified as obstacles to proper disposal. In Study 2, we used the disrupt-then-reframe technique to successfully overcome these obstacles and promote proper disposal of used oil. The results underscore the usefulness of empirically validated persuasion techniques in changing behavior via mass media.