Drawing together his work from four decades, Phillip Bricker provides a comprehensive account of modal reality - the realm of possible worlds - from a Humean perspective, with excursions into neighboring topics in metaphysics. Many of the chapters in this volume focus on aspects of David Lewis's metaphysics and his defence of modal realism, sometimes further developing and defending Lewis's views, sometimes deviating from them in substantial ways. The volume is presented in four parts: part one sketches an account of reality as a whole, both the mathematical and the modal, defending a form of plenitudinous realism; part two presents and defends a realist theory of concrete possible worlds with an absolute ontological distinction between the actual and the merely possible; part three presents and defends a Humean account of modal plenitude, formulating and endorsing principles that guarantee a plenitude of recombination, of possible structures, and of alien contents; and part four applies the Humean account to truthmaking, mereology, spacetime, and quantities. An uncompromising Humean, Bricker shows that holding fast to Humean strictures leads to views that differ in radical ways from those prevalent among contemporary metaphysicians.