ObjectivesRigorous tests are not usually applied to determine whether mass media campaigns that promote responsible drinking are useful, that is whether they lead to responsible drinking or not. In two experiments, we investigated the effectiveness of a mass media campaign that runs in Germany since 2009. This campaign used posters, which emphasized negative alcohol-related outcome expectancies and challenged the positive expectancies. Based on models of alcohol use, we investigated the influence of the campaign on alcohol-related outcome expectancies, implicit and explicit attitudes, and drinking intentions. DesignIn Experiment 1, we investigated alcohol-related outcome expectancies via ratings and response latencies among 81 young adult light drinkers. Employing an affective priming task, Experiment 2 was designed to assess implicit attitudes before and after mass media campaign exposure among 83 young adult light drinkers. In both experiments, the effects of the posters were investigated before and after poster exposure as well as compared to a control group. ResultsExperiment 1 revealed that the campaign affected only the implicit associations of young adult drinkers, whereas explicit outcome expectancies remained unaffected. Experiment 2 showed that implicit attitudes towards alcohol were turned into more negative ones, but explicit attitudes as well as drinking intentions were not influenced. ConclusionsThe mass media campaign was deemed effective even though its influence occurred on an implicit level. This research highlights the need for experimental investigations of mass media campaigns. Reasons that the findings were obtained on an implicit but not on an explicit level are discussed.