This book offers a detailed defense of a metaphysics of Platonic universals and a conception of particular objects that is coherent with said metaphysics. The work discusses all the main alternatives in metaphysics of properties and tries to show why universals are the entities that best satisfy the theoretical roles required for a property. The work also explains the advantages of Platonic over Aristotelian universals in the metaphysics of modality and natural laws. Moreover, it is argued that only Platonic universals are coherent with the grounding profile required for universals. The traditional objections against Platonism are discussed and answered. The third part of the book, finally, offers a conception of particular objects as nuclear bundles of tropes that is coherent with the Platonic ontology of universals. This book is of interest to anyone that wants to understand the current -and intricate- debate in metaphysics of properties and its incidence in many other areas in philosophy.