Turkey has been a critical case to study to assess the impact of EU conditionality on non-member states, but has lost its visibility following the debates on the detachment of Turkey from the EU gradually since 2005.This book studies Turkey–EU relations in the area of foreign policy from 1987 when Turkey applied for full membership and expanding to the present-day retrenchment of Turkey from the EU. It provides a unique perspective in looking to explain the entirety of the EU–Turkey relations during this period, covering both transformation and retrenchment of Turkish foreign policy from the EU requirements. The book further illustrates that the conditionality mechanism is still relevant to study EU–Turkey relations, and when applied systematically, can map both attachment and detachment from the EU. It is also critical to understand how Turkey has distanced itself from the EU gradually and incrementally. This book is of key interest to scholars and students of EU foreign policy, Turkish foreign policy, conditionality, foreign policy analysis, Turkish–EU relations, the ENP and more broadly to international relations.