The thesis of this book is that Williams played a key role in the development and revival of analytic metaphysics. This book begins with an account of Williams' approach to philosophy given the rise of realism in the early twentieth century, with a focus on his use of induction and parsimony to argue for metaphysical theses such as metaphysical realism and metaphysical naturalism. It explains his critique of logical positivism and his defence of an empirical conception of metaphysics, which in turn reveals how he took himself to be standing up to rising anti-metaphysical trends. This book then expounds—within the framework of his empirical metaphysics—his one-category trope ontology and its origins, arguing that his systematisation of the concept of an abstract particular (or trope) is his most novel contribution to analytic ontology. This book further presents an original interpretation of his account of concrete objects and abstract universals, engaging with current debates in the metaphysics of properties—sometimes defending Williams, sometimes correcting misinterpretations, sometimes critically reassessing his views. This book also explains his defence of the four-dimensional manifold of time and his objections to competing theories such as the growing block theory and presentism (incorporating recently posthumously published work in The Elements and Patterns of Being, ed. A.R.J. Fisher, 2018), with up-to-date references to the latest work in the metaphysics of time. Lastly, this book analyses Williams's influence on later philosophers such as Lewis and Armstrong (and others in Australia), drawing from correspondence between Williams, Lewis, and Armstrong, and evaluates his place in the history of analytic philosophy, concluding that he played a key role in the development and revival of analytic metaphysics.