"McGruff," the most wide-ranging and most evaluated crime prevention campaign, has apparently been successful in promoting various aspects of crime prevention competence among a wide range of citizens. Moreover, the campaign has been a centerpiece for a host of allied preventive efforts locally, statewide, and nationally. McGruff's effectiveness may be due to the use of formative research in its design and to the integration of interpersonal and community-level support with the media components. Subsequent campaigns could be improved with such use of theoretical models of communication and persuasion in their design. A more detailed examination of audience characteristics should be included in campaign design as well, and the news media should have a critical role in campaign dissemination. There is a general lack of continuing, systematic evaluation of crime prevention programs which leaves a gap in knowledge about why some techniques work and others do not. 42 references.