Diamandopoulos was named the president of Sonoma State University in 1977 and served until 1983 when he was forced to resign after continuing controversy including multiple censures and a faculty vote of no confidence.
[3] Seeking to improve the school's academic reputation, Diamandopoulos raised tuition and reduced faculty.
[4][5] His own compensation package remained unaffected by cuts and included a Mercedes-Benz, a condominium in Manhattan, and the presidential residence on the Adelphi campus.
[6] An investigation of the school's finances showed that it was a customer of the insurance company run by Ernesta G. Procope, who also served as the head of Adelphi's board.
[10] In December 1998, Diamandopoulos was named special assistant to John Silber, the president of Boston University.