David K. Lewis (1941-2001) was unquestionably one of the most important analytic philosophers of the twentieth century, writing papers and books, largely but not exclusively in metaphysics, that set the intellectual agenda across a huge variety of topics in the last three decades. Some twenty years after his death, this collection of essays reflects the historical importance of Lewis's work by bringing together a range of scholarly reflections on his work. The essays consider a range of topics including the nature of metaphysics, the epistemology of necessary truths, possibility, naturalness, supervenience, time travel, causation, semantics, and ethics. Several of them draw on an exciting new body of material in the Lewisian corpus, his extensive correspondence, recently published in two volumes (OUP, 2020). The wide-ranging topics of these essays illustrate the impressive extent of Lewis's thought and his reach across most areas of analytic philosophy. The chapters collected in this volume adds to the increasing literature on the philosophy of David K. Lewis and will be an important book for those examining his role in the history of analytic philosophy.