This chapter examines moderate modal skepticism, a form of skepticism about metaphysical modality defended by Peter van Inwagen in order to blunt the force of certain modal arguments in the philosophy of religion. Van Inwagen’s argument for moderate modal skepticism assumes Yablo’s (1993) influential world-based epistemology of possibility. This chapter raises two problems for this epistemology of possibility, which undermine van Inwagen’s argument. It then considers how one might motivate moderate modal skepticism by relying on a different epistemology of possibility, which does not face these problems: Williamson’s (2007) counterfactual-based epistemology. Two ways of motivating moderate modal skepticism within that framework are found un...