In Fall 1990, a knowledge, attitude, belief, and practices (KABP) survey was administered to a representative sample of residents of St. Vincent and the Grenadines, an island nation in the Eastern Caribbean. The KABP questionnaire contained a large number of questions that could reasonably be expected to be related to whether or not people use condoms. To a certain extent, each of these questions can be viewed as an attempt to assess one of the variables identified by one or more theories of behavior and behavior change. More specifically, questions on the KABP were identified as possible indicants of AIDS knowledge, cues to action, perceived susceptibility, perceived severity, perceived (locus of) control, perceived normative pressure, and condom use outcome expectancies. Statistical analyses indicated that some, but not all, of these variables were related to condom use among sexually active adults. In particular, the analyses indicated that perceived normative pressure to use condoms was the single most important determinant of condom use behaviors on St. Vincent. The implications of this finding for designing mass-media campaigns to increase condom use is discussed, and a campaign that attempts to change condom use by influencing perceived social norms is strongly recommended.