In contemporary Northern Ireland, more than two decades after the peace agreement that ended the thirty-year sectarian violence known as 'the Troubles' the risk of a return to violent conflict is not only present but growing. Drawing on ethnographic fieldwork, comparative research, and over 110 hours of face-to-face interviews with a diverse range of political, academic, civil society, and community actors across Northern Ireland, A Troubled Sleep revisits one of the world's most deeply divided societies to analyze Northern Ireland's current vulnerabilities, and points of resilience, as an allegedly 'post-conflict' society. By examining the Northern Ireland example, Waller presents deep insight into what happens when identity politics prevail over democracy, when a paralysis in governance leads to a political vacuum for extremist voices to exploit, when de facto social segregation becomes normalized, when acclimatization to violence becomes a generational legacy, and when questions of who we are become secondary to who we are not.