Mexico's revolution of 1910 ushered in a revolutionary era: during the twentieth century, Mexican, Russian, Chinese, Cuban, Nicaraguan, and Iranian revolutions shaped local, regional, and world history. Because Mexico was at the time a rural and agrarian country, it is not surprising that historians have concentrated on the revolution in the countryside where the rural underclass fought for land. This book uncovers a previously unknown workers' revolution within the broader revolution. Working in Mexico's largest factory industry, cotton textile operatives fought their own fight, one that challenged and overthrew the old labor regime and changed the social relations of work. Their struggle created the most progressive labor regime in Latin America, including but not limited to the famous Article 123 of the 1917 Constitution. Revolution within the Revolution analyzes the rules of labor and explains how they became a pillar of the country's political system. Through the rest of the twentieth century, Mexico's land reform and revolutionary labor regime allowed it to avoid the revolution and repression experienced elsewhere in Latin America.