The Neighbor Who Might Kill You: Encounter and Difference in Urban Turkey is a book project primarily concerned with how gendered sectarian, ethnic and national differences are viscerally experienced and produced by ordinary people in the polarizing political environments of cities across Turkey. In this collaboration with Anna J. Secor, we analyze narratives of how differences that were previously unknown or unmarked have come to be recognized based on the research we conducted between 2013 and 2016 (funded by the National Science Foundation). While this recognition enables possibilities for pluralistic coexistence, it also unleashes a potential threat of violence. We locate the emergence of difference in and through the affective encounters of everyday urban life, most notably in the interactions between neighbors that come to know and feel the ethical obligation to respond to each other in the spaces of homes, apartment buildings, and across the streets of neighborhoods. We show how difference is embodied and localized in affective and ethical encounters with others. Traversing the sites of everyday urban life, we analyze how encounters create openings for receptive ethical engagement at the same time as they frequently collapse into anxious antagonisms that exacerbate the precarity of marginal populations.