In recent years, metaphysicians have been taking an increasing interest in the grounding relation - the relation that exists, roughly, when one thing holds in virtue of something else holding, a non-causal metaphysical priority relation. Thoughts about grounding are also of central importance in the metaphysical parts of metaethics (indeed, often the metaethical Euthyphro contrast is mentioned as a paradigm of a debate over grounding). In this seminar, we will discuss some of the general contemporary discussion of grounding in metaphysics, and some of its implications for metaethics.  (Team taught with David Enoch)