Forty-five participants diagnosed as having specific phobia of spiders were randomly assigned to one of three treatment groups: (a) computer-aided vicarious exposure; (b) therapist-delivered live exposure; (c) relaxation placebo. Each group received three 45-minute sessions. Phobic symptom severity was measured at pretreatment, post-treatment, and at a 3-month follow-up assessment with the Spider Questionnaire, Fear Questionnaire, Phobic Targets and Work Adjustment Ratings Scale, and a Behavioral Assessment Test with Subjective Units of Distress Rating Scale. The results showed that the computer-aided vicarious exposure was an effective treatment for spider phobia and comparable to live exposure therapy in significantly reducing phobic symptoms. Both the computer and live exposure treatments were more effective than the relaxation placebo treatment.