On July 23, 1967, the Detroit police raided a blind pig (after-hours drinking establishment), touching off the most destructive urban riot of the 1960s. It took the U.S. Army, the Michigan National Guard, the Michigan State Police, and the Detroit police department—17,000 men—more than a week to restore order. When all was done, the riot had claimed 43 lives (mostly Black) and resulted in nearly 700 injuries. Over 7,000 individuals were arrested, with property damage estimates over $75 million. Yet, Detroit had been lauded nationally as a "model city" in the governance of a large industrial metropolis. On the 40th anniversary of this nation-changing event, we are pleased to reissue Sidney Fine's seminal work—a detailed study of what happened, why, and with what consequences.