Leader development serves as a strong focus in the mission statements of many business school programs. Looking at business school leader development programs through the lens of adult learning theory, we assert that there is an overreliance on cognitive training (e.g., lecture) as the primary form of education used in preparing future business leaders, neglecting other relevant learning orientations. In response, we advance a comprehensive model of business leader education and training that incorporates and integrates five primary orientations to adult learning (cognitivist, behaviorist, humanistic, social cognitive, constructivist). We argue that other professional training curricula, most notably, medical school and military education, draw more fully on these five orientations to adult learning and that these represent comparative models for what business schools could be doing in leader development. We conclude by providing concrete suggestions for how business educators might apply the model in their own programs.