The book develops a robust and holistic theoretical understanding of the intrinsic security concerns which lie at the heart of the protracted conflict in Cyprus. The work offers a theoretical grounded account of intractability in Cyprus by unfolding the rationale and prevalence of competitive approaches held by Greek and Turkish Cypriots alike. The analysis explains how crude security interests have given rise to an existentialist security dilemma that has prevented Greek and Turkish Cypriots, and their security guarantors, from reaching a durable settlement. The book contains a systematic critique of the breadth and depth of security concerns embedded in the proposed federal bi-zonal framework for Cyprus, uncovering the impetus and rationale of the underlying insecurities that prompt the Greek and Turkish sides to compete on a series of state-building aspects, including the opposing understandings of self-determination and sovereignty, the competitive underpinnings of federal institutional design, and the problematic role of third-party involvement. The book ultimately unravels a deeper and more pragmatic understanding of how competitive security considerations and systemic uncertainty link up to ethno-federal design in post-conflict environments. This book will be of much interest to students of conflict studies, federalism studies, statebuilding, European politics and International Relations.