Renowned Marxist scholar Michael Löwy offers an indispensable assessment of an enduringly fascinating revolutionary. Vibrant, insightful, and wide-ranging, Löwy’s essays illuminate the heroic, tough-minded idealist and martyr, Rosa Luxemburg. Active in the labor and socialist movements of Germany, Poland, and Russia, Luxemburg had international standing as an original and sharp-minded theorist during her life and remains one of the most admired and studied revolutionaries in the Marxist tradition. Löwy follows Luxemburg in blending diverse intellectual disciplines—philosophy, history, political science, sociology, anthropology, and economics—to make sense of global realities in her time and our own. Luxemburg’s creative intellectual endeavors were shaped by her genuine devotion to the free development of all people, and her fierce opposition to all forms of tyranny and authoritarianism. These commitments guided her analyses of exploitation and mass struggle, the dynamics of trade unions and of bureaucracy, the origins and impacts of economic crisis, the nature of war and imperialism, and the interconnections of reform and revolution. In accessible and stimulating prose, Löwy explores Luxemburg’s many political and theoretical contributions, as well as her links to revolutionaries including Karl Marx, Vladimir Lenin, Antonio Gramsci, Georg Lukács, José Carlos Mariátegui, and Leon Trotsky. Through Löwy’s expansive engagement with Luxemburg‘s political trajectory and influence, we are able to see her wrestle with political problems that remain relevant today.