This article explores the concept of federalism and its relevance in today's world. It discusses different types of federal systems, historical traditions of federal thought, the formation of federal states, and the division of powers within federal governments. The research also delves into intergovernmental relations, constitutional amendment processes, judicial review in federal systems, and how federations manage policy responsibilities. The main goal is to understand how federalism works in different contexts and to highlight the key principles and challenges of federal governance.