Based on extensive formative research in the three Eastern Caribbean countries of St. Lucia, St. Vincent and the Grenadines, and Grenada (Fishbein, Middlestadt,&Trafimow, 1993; Fishbein, Trafimow, et al., 1993), a three‐nation, mass media, condom use campaign was developed. In order to assess the impact of the campaign, a follow‐up survey was conducted in St. Vincent and the Grenadines. This paper examines the effectiveness of the campaign by comparing responses on this survey by respondents who were or were not exposed to the campaign. A statistically significant impact of exposure to the campaign was obtained, indicating that a well‐designed, empirically based, mass media campaign can be an effective tool in the battle to prevent the spread of