Oxford Studies in Metaphysics is a major new series dedicated to the timely publication of new work in this highly fertile field of philosophy. The subject is broadly construed, taken to include not only perennially central topics (modality, ontology, and mereology; metaphysical theories of causation, laws of nature, persistence through time, and time itself; and realism and anti-realism in the many senses of these terms); but also the rich clusters of metaphysical questions that open up within other subfields, such as philosophy of mind and philosophy of science (questions about supervenience and materialism, the nature of qualia, mental causation, metaphysical implications of relativity and quantum physics, mereological theories of biological species, and so on). Besides independent essays, volumes will often contain a critical essay on a recent book, or a symposium that allows participants to respond to one another's criticisms and questions. Each future volume shall also include an essay by the winner of the Oxford Studies in Metaphysics younger scholar award, a prize inaugurated with this first issue.