Based on Epstein's (1994a) cognitive-experiential self-theory, two new training interventions were designed to teach students about gay, lesbian and bisexual issues. The efficacy of these theoretically based interventions was assessed in a short-term (7-week, three occasion) longitudinal study. Fifty undergraduate psychology students were randomly assigned to one of three treatment groups: Rational Training, Experiential Training, or Control Group. A residualized change score procedure was used to analyze change in levels of sexual prejudice and affect across the three types of measurement (pre-test, post-test, and follow-up). A 3 (Rational Training, Experiential Training, Control Group) x 2 (Low Sexual Prejudice, High Sexual Prejudice) MANOVA revealed that after the training, participants in the Experiential Group (affective training) had more accepting attitudes toward homosexuality compared to the Control Group. In addition, participants in the Experiential Group experienced more positive affect compared to the Rational and Control Groups and experienced more negative affect compared to the Rational Group. Findings are discussed and suggestions for future research are provided.