Reiss taught at Marquette University (1957–1963) and then at Fordham (1963–1985). From 1969 until he left Fordham to become President of Saint Michael's (from which he retired as President Emeritus in 1996) he worked in administration as Dean, Vice President, and Executive Vice President.
Reiss taught at Marquette University between 1957 and 1963 and then at Fordham from 1963 to 1985. From 1969, he worked in administration as Dean, Vice President, and Executive Vice President until his appointment as the President of Saint Michael's, where he later retired as President Emeritus.