By the middle of the twentieth century, American universities had evolved into powerful institutions with aggressive cultural agendas. Renewed interest in the arts provided a platform for composers employed by these universities to grow into powerful civic leaders. This article investigates the contributions of four modernist composers--Walter Piston, Roger Sessions, William Schuman, and David Diamond,--who held academic and administrative posts at Harvard University, Princeton University, the University of California at Berkeley, and the Juilliard School of Music. During this period, these four composers used their academic positions to shape American classical music culture--not through their compositions--but by overhauling music departments, authoring textbooks, and extending the reach of universities and conservatories far beyond the campus walls. This project relies on primary and secondary sources, weaving together academic records, administrative reports, and composer correspondence into a narrative of educational reform, cultural patronage, and even urban renewal. This article endeavors to widen the historiographic focus on postwar composers like the Four to reconsider their relevance as music educators, cultural authorities, and practitioners of modernism outside of the concert hall.