In this chapter I explore a number of different proposals for how to define ‘divine determinism.’ I settle on one to guide the rest of the book, which was first offered by Heath White. On this account, divine determinism is the conjunction of two claims: (i) The facts about God’s will wholly determine every other contingent fact and (ii) the facts about God’s will explain every other contingent fact. I then turn to a brief overview of some motivations for divine determinism. I begin with philosophical motivations, including motivations arising from consideration of the principle of sufficient reason, divine sovereignty, divine power, divine knowledge, divine aseity, and divine providence. I then turn to motivations that are more closely tied to particular religious traditions, including ones related to prophecy, scriptural authorship, and specific scriptural passages. Finally, I investigate two different varieties of divine determinism: primary divine determinism and Edwardian divine determinism.