The first English translation of this seminal text. “It will give the American public the opportunity to hear Rosa Luxemburg speak for herself in her confrontation with Karl Kautsky on the crucial questions of the General Mass Strike and on the relationship of spontaneity to organization, as well as on the unity of theory and practice. This crucial 1910 debate in German Social Democracy led to Luxemburg’s revolutionary break with Karl Kautsky and foreshadowed the collapse of the Second International at the outbreak of World War I. Also included here are her concluding remarks from Attrition of Collision in that continuing debate, where she extended her critique of the opportunism which was corroding the German Social Democracy to an attack on its pusillanimity i the fight against imperialism.