In 1974, the Florida Board of Regents chose Marston as the seventh president of the University of Florida located in Gainesville, Florida; he undertook the presidency during a time of economic recession, state budget cuts and increased demand for private funding of the university. During his ten-year tenure, the university matured into one of the United States' ten largest single-campus universities and one of the five most inclusive in the scope of its academic programs, with significant growth in its sponsored research activities, and notable advancement of the university's academic excellence and reputation. Marston's accomplishments as university president included the organization of a non-profit corporate structure for the management of Shands Hospital, helping establish the State of Florida's Eminent Scholars Program, dramatically increasing the university's private financial support, developing plans to recruit National Merit Scholars and National Achievement Scholars, and laying the organizational foundation for the University of Florida's eventual membership in the Association of American Universities (AAU).