For nearly forty years now, Frankfurt cases have served as one of the major contributors to the compatibilist's cause with respect to moral responsibility. These cases typically involve a causally preempted condition that is supposed to guarantee a choice without causing it. This has had the effect of softening up some to the idea that determinism does not exclude moral responsibility simply in virtue of guaranteeing a unique future. I believe that these traditional Frankfurt cases adequately support this cause. But I also believe that the traditional versions of Frankfurt cases suffer from some rhetorical defects.My strategy is as follows. First, I want to respond to a dilemma that has been raised by some libertarians against arguments utilizing Frankfurt cases. This dilemma has the effect of raising a question-begging charge against such arguments. Part of my response is to draw attention to the relevant principle that I think Frankfurt cases should really target, a principle slightly different from Harry Frankfurt's original Principle of Alternate Possibilities. Second, I elaborate and defend the claim that traditional Frankfurt cases involve causal preemption.