ABSTRACT The 1960s and 1970s are often identified as a period of tension and explosive conflict between teachers’ unions and communities of color. Instances of this can be found across the United States: in New York City, Chicago, Detroit, Philadelphia, Newark, St. Louis, among others. What fails to be documented in the literature are instances of alignment between teachers’ unions and communities of color. The case of the 1970 New Haven Federation of Teachers (NHFT) is an instance of such an alignment. This article demonstrates that this resulted from New Left teachers taking co-leadership of the NHFT, bringing in ideas of participatory democracy and preexisting neighborhood bonds from prior anti-racist social movement and community organizing work. This distinguished the NHFT from other teachers’ unions of the time period, where the New Left was either absent or marginalized. Whereas teachers’ unions across the United States were often in high pitched conflict with communities of color as most infamously represented by 1968 Ocean Hill-Brownsville, the NHFT consciously formed an anomalous alliance and an alternative vision of education, pushing for joint teacher-community control of schools. This article thereby demonstrates the importance of radical ideas for decisively shaping the direction of labor unions.