WE sometimes have occasion to evaluate a person with respect to his life as a whole. We might, for example, wish to say of a person after his death that he had lived a most prudent life, that he had always acted so as to best coordinate and satisfy his past, present, and future desires. To the extent that we ourselves value prudence-desiring that our lives live up to their full potential, developing as integral wholes-we may ask, when faced with an array of alternative actions: which is the most prudent act? which act would contribute the most to my life? In this paper, I will attempt to outline an analysis of prudence. The analysis seeks to apply the concept of prudence primarily to a person with respect to his life as a whole, and only derivatively to the individual acts that make up that life. Partly for this reason, the theory of prudence that I will present could be applied by an agent at the time of acting only if he were extraordinarily knowl-edgeable about the facts-past and future, actual and possible-that are relevant to his life. The chief purpose of this paper is not to argue for specific prudential maxims that would be useful to an agent at the time of acting, but rather to reveal what I take to be the basic structure underlying any adequate theory of prudence. However, as I hope some of the examples throughout this paper will suggest, the theory of prudence here presented is not without practical implications for a normative theory of decision-making. I do not wish to claim that the concept of prudence that will emerge from my analysis will coincide with any of the uses of the term'prudence'in ordinary language: ordinary usage is beside the point when it comes to evaluating the interest of the analysis. In