"Federalism" is an important political and legal book written by the famous Brazilian figure of Lima, S. de Magalanche (Sebastian de Magalanche). In this work, the author examines the basic principles of federalism and its influence on modern state formations. The book reveals the history, essence and advantages of federalism as a system of governance, and also provides an analysis of various models of federalism in the world. Thanks to a deep and comprehensive approach to the topic, the author helps the reader better understand the essence of federalism and the impact of its application on the development of the state. The book "Federalism" will be a useful source of knowledge for politicians, scientists and anyone interested in modern political theory.