Heidegger’s treatment of the Other in Being and Time has been heavily scrutinized by Levinas, his former follower, foremost critic, and one of the major theorists of alterity. In particular, Levinas has criticized Heidegger’s ontological approach to the Other, which, he argues, inevitably reduces the Other to more of the same. The implications of this claim are dire; Levinas accuses Heidegger’s attitude towards the Other of being assimilationist, imperialistic, and ultimately unethical. The existing literature on the controversy between the two thinkers is ambivalent. While many scholars tend to side with Heidegger, citing Levinas’ misinterpretations of his former mentor, few regard Heidegger’s account of the Other as wholly unproblematic either. My goals in this paper are twofold. First, I reconstruct Levinas’ critique of Heidegger as it is expressed in Totality and Infinity. By demonstrating that Levinas engages with Being and Time more closely than the literature suggests, I argue that it is necessary and valuable to renew our attention to Levinas’ critique, taking seriously his grievances instead of dismissing his interpretation of Heidegger as hasty or misguided. In the second half of the paper, I argue that Heidegger’s concept of conscience is a promising ethical response to Levinas’ complaints about Heidegger’s ontological prioritization of the self, especially when considered in light of Haugeland’s interpretation of Heidegger. I conclude the paper by exploring what an ethics of alterity might begin to look like based on the dialogue between Heidegger and Levinas. Given that both thinkers insist that ethics begins with a radical destabilization of the self in the face of the unknown, I suggest that self-understanding is an essential component of what we owe to the Other.