Almost thirty years ago, in an attempt to undermine what he termed "the principle of alternate possibilities" (the thesis that people are morally responsible for what they have done only if they could have done otherwise), Harry Frankfurt offered an ingenious thought-experiment that has played a major role in subsequent work on moral responsibility and free will. Several philosophers, including David Widerker and Robert Kane, argued recently that this thought-experiment and others like it are fundamentally flawed. This paper develops a (...) new Frankfurt-style example that is immune to their objections. [Reprinted in Laura Waddell Ekstrom, ed., Agency and Responsibility: Essays on the Metaphysics of Freedom (Westview Press, 2001), pp. 241-54; and in John Martin Fischer, ed., Free Will, Vol. III (Routledge, 2005), pp. 330-42.]. (shrink)