This chapter presents the argument that leadership is not always effective, even though we know a great deal about what makes leadership effective. Consequently, we are asking the wrong question when we inquire into what makes leadership effective. A more interesting question is that when we know so much about effective leadership, why are leaders sometimes unable to exercise effective leadership? Why do not they do as they should? The answer discussed here is that leadership is often ineffective because people are imperfect, including leaders. Therefore, there are individual and organisational barriers to effective leadership, as well as constraints in the environment. Better education and training programmes for leaders, as well as more r...