This book seeks to demystify the persistence of the Anglo-American Special Relationship (AASR) in the post-Cold War era by constructing a new theory of alliance persistence. This theory of alliance persistence not only has stronger explanatory power than the predominant model of interests and sentiments, but also opens a new way for understanding what factors have prevented the AASR from collapsing. This innovative new volume fills the gap in AASR literature by focusing on the important role of institutionalization in sustaining the AASR, a factor that has been significantly overlooked in existing academic research.