As a system of Public International Law (PIL), International Refugee Law (IRL) diverges from those that evolved concurrently in certain distinct ways. Though internationally recognised, with a widely ratified Convention, and with complementary regional instruments and municipal legal regimes that require adherence to its fundamental tenets, the absence of clear instances of the attribution of international State responsibility is conspicuous. This book provides a thorough inquiry into the deficiency that makes IRL so exceptional among systems of PIL, through an in-depth analysis of the evolving relationship between IRL and general PIL from the late 19th century to the present day.