This fully revised and updated fourth edition of a highly successful text in this academic field examines the key traditions in political thought while relating them to the contemporary world. Each chapter discusses a group of related terms and concepts and sheds light on how they are used by different thinkers and schools of thought. The book systematically builds an understanding of both classical and modern theory by revisiting a wide range of important thinkers, from the time of Aristotle, Rousseau, Marx, and Mill to the present day. This edition further covers the global dimensions of political thought—with a new chapter on international issues such as security and war—and non-Western approaches to political debates and conflicts.