Effective campaigns are desperately needed to combat the serious social problem of teen pregnancy. However, public health campaigns are most often noted for failures, rather than successes. One reason for a campaign failing to have the intended effect is lack of theoretical guidance at the formative evaluation stage. The study reported here is a theoretically-based formative evaluation with inner city teens. Six focus groups were conducted to determine knowledge, attitudes, beliefs, and recommendations for effective campaigns to deter teen pregnancy. The results indicate that campaign messages need to combat positive attitudes toward pregnancy, negative attitudes toward birth control, the perception of personal invulnerability, and emphasize the negative consequences of sexual intercourse. This study's findings also suggest that campaigns with these messages need to start at an early age in order to effectively prevent teen pregnancy.