As nutrition officials face the need to address widespread chronic obesity and its associated diseases, many have turned to media campaigns as a strategy for reaching large audiences. In the past, such efforts have had mixed results. Examples of successful and unsuccessful major public health campaigns are presented, including a small number related to diet. One implication of the analysis of those cases is the importance of obtaining high levels of exposure to messages. Several strategies for maximizing exposure are elaborated, including the use of paid advertising, relying on donated time, and earning coverage through media advocacy.