Discussion teaching–the foundation of the Harvard Business School’s renowned case method of instruction–is a powerful tool for developing skills as well as conveying knowledge. In the give and take of discussion, students go beyond abstract understanding to the active application of important principles. They are confronted with the same kind of ambiguous, many-sided problems they will face in their professional lives. The elements of great teaching can be identified and consciously practiced. Many of the essays describe the building blocks of successful group leadership: negotiating a contract governing the conduct of the group; orchestrating a constructive process of questioning, listening, and responding; encouraging independent thinking; and guiding participants toward useful roles in their interaction with one another. The other chapters in the volume cover the ethical considerations of discussion teaching, the special challenges of teaching technical material using this method, and one pioneering effort to introduce a participative mode of medical education.