This book explores the dispositional and categorical debates on the metaphysics of properties. It defends the view that all fundamental properties and relations are contingently categorical, while also examining alternative accounts of the nature of properties. Drawing upon both established research and the author's own investigation into the broader discipline of the metaphysics of science, this book provides a comprehensive study of the many views and opinions regarding a most debatable topic in contemporary metaphysics. Science in Metaphysics will be of interest to metaphysicians of science, analytic metaphysicians and philosophers of science and physics alike.