The New York City Teachers Union shares a deep history with the American left, having participated in some of its most explosive battles. Established in 1916, the union maintained an early, unofficial partnership with the American Communist Party, winning key union positions and advocating a number of Party goals. Clarence Taylor recounts this pivotal relationship and the backlash it created, as the union threw its support behind controversial policies and rights movements. Taylor’s research reaffirms the party’s close ties with the union—yet it also makes clear that the organization was anything but a puppet of Communist power.