James P. Cannon was a founder of the Communist Party of the United States after World War I and one of its central leaders in the 1920s. Breaking with the Stalinised CP in 1928, he founded the American Trotskyist movement and played a decisive role in building it for over three decades. The outstanding figure produced by the Marxist movement in the United States, his efforts to build a revolutionary workers’ party in the heartland of world capitalism are without precedent in their sheer duration over so long a period and in the face of such tremendous pressures. The achievement of world socialism, to which Cannon dedicated his life, remains before us but socialists everywhere can gain inspiration and learn valuable lessons from a study of the rich legacy of his writings and speeches. This book provides a brief introduction to Cannon’s life and work and presents a number of his writings from the 1950s and 1960s, otherwise not readily available.