Background: Educating medical students about how to effectively counsel patients with negative health behaviors (i.e., lack of exercise, smoking) is vitally important. Behavior change counseling is a promising method that can be used by physicians to encourage positive changes in health behaviors. Purpose: To examine the effectiveness of a 2 h workshop in behavior change counseling for medical students. Methods: This study used a pre-post control group design with 35 second-year medical students who were randomly assigned to participate in a behavior change counseling intervention or wait-list control group. Student knowledge and attitudes were assessed using multiple choice items and open-ended question prompts. Student skills were assessed via performance in a standardized patient encounter rated using the Behavior Change Counseling Index (BECCI). Results: Student attitudes toward behavior change counseling were positive at both pre-and post-test assessment in both groups. Knowledge scores and BECCI total scores showed significantly greater improvement in the intervention group compared to the wait-list control group. Conclusions: This study found that a brief educational intervention had a positive impact on medical students' knowledge and skills in behavior change counseling, and that student attitudes about the counseling method were very positive.