 Otávio Bueno and Scott Shalkowski (2015) adopt modalism about modality. They maintain that there is no reductive analysis of modality in terms of non-modal facts or properties. For arguably one cannot reduce the truth of “It is possible that \(P\)” to “It is true in some world, \(w\), that \(P\)” without wondering whether or not \(w\) itself is possible or impossible. The epistemological task for Bueno and Shalkowski is thus to provide an account of how we come to know modal truths while accepting a primitivist view of modality. In this way, Bueno and Shalkowski aim to meet the Integration Challenge.