A pledge card program designed to motivate safety belt use was implemented at a Baptist church in Blacksburg, Virginia. The intervention consisted of an educational insert and pledge card which were included in church bulletins on one Sunday morning. The insert described the risk of injury on highways and added a prompt for parents to provide positive role models for their children by wearing safety belts. The pledge card included a statement that signers would buckle their safety belts for four weeks when traveling. Data were collected at predetermined time periods on Sunday mornings between January 29 and May 20, 1984. The study consisted of five phases: Unannounced Baseline, Announced Baseline, Pledge Period, Follow-Up, and Long-Term Follow-Up. Ten percent of 441 individuals attending church when the pledge cards were distributed signed and returned a pledge card. Results revealed that shoulder belt use of pledge card signers increased significantly after signing the pledge cards, while shoulder belt use of non-signers did not significantly increase. In addition, shoulder belt usage of females was significantly higher than shoulder belt usage of males following the announcement of the research and throughout the remainder of the study. Evidence of participant reactivity is also presented. Suggestions are made for mitigating reactivity, for achieving greater impact on males, and for motivating more males and females to sign pledge cards. / Master of Science