Weakness of will seems to be an inherent part of the human condition. We know what we ought to do and how often we knowingly, willingly fall short in actual practice. How can this be explained and what challenges does it present to systematic explanations of intentional actions? In this clear, incisive and well written inquiry, philosopher Keith Wyma subjects the thought of three prominent intentional theorists, R.M.Hare, Donald Davidson and Thomas Aquinas, to the crucible of reason to see whether and how they can account for weakness of will. Wyma is careful to clarify which actions count as incontinent or the result of weakness of will; they must be performed intentionally even as they are judged as something that ought not to be done. His in-depth study of Hare, Davidson and Aquinas on this important issue is a major contribution to understanding practical rationality and intentional action.