The main body of this Element, about Kant's theory of conscience, is divided into two sections. The first focuses on exegesis of Kant's ethics. One of the overarching theses of this section of the Element is that, although many of Kant's claims about conscience are prima facie inconsistent, a close examination of context generally can dissolve apparent contradictions. The second section of the Element focuses on philosophical issues in Kantian ethics. One of the overarching theses of this section of the Element is that many positions traditionally associated with Kantian ethics, including the denial of moral luck, the nonaccidental rightness condition, and the guise of the objectively good, are at variance with Kant's ethics.