Book excerpt: This book conceives federalism not as a static institutional architecture, but as a dynamic formation always in flux. This may entail processes of federalization, but in some cases also lead to de-federalization. It looks at emerging federal structures worldwide and analyses federal structures: their emergence, operation and categorization. The contributors highlight that the “emergence” of these federal structures has multiple facets, from the recognition of ethnic diversity to the use of federalism as a tool of conflict resolution. Identifying and categorizing processes of federalization and defederalization in a variety of cases, the book provides much needed empirical and theoretical discussion on emerging federal structures and the changing nature of federalism in the post-Cold War era.