Negotiation classes are one way in which many of today's managers try to develop negotiation skills. Despite the popularity of such courses, relatively little research has assessed their effectiveness in improving trainee self-confidence and posttraining transfer. The results of 2 data collection efforts indicate that students in a typical negotiation-training course integrating the principles of instructional design believed that they had improved their negotiating skills and confidence, adopted more integrative conflict management styles, and implemented their newfound skills in important real-world negotiations. These perceived changes persisted over time. (Contains 3 tables.)