This book is a result of an independent study to explain the Ethiopian federation: its making, its features, and its theoretical and practical challenges. The constitutional pact theory of federalism guided the study. The analysis followed the political and ideological approach to the study of federalism. The constitutional recognition of the national diversity, where not only all the nations, nationalities, and peoples of the federation have the right to self-determination but also all equal, and each is sovereign, was the animating element throughout the study. The book recounts the international and local backgrounds to national self-determination and the political dynamism during the process of the formation of the federation. It explicates the conceptual underpinnings of the federalization process and defines Ethiopian federalism with a new recognition theory of federalism that it suggests. It articulates the features of the federation in detail. Also, it analyzes the conceptual and practical challenges of the federation. It is written with reserved judgments to allow general-purpose readers and students of federalism to make a well-informed understanding out of the dissertation. The work could be a contribution to the study of federalism.