In 1964, before he completed his PhD, Stan O'Connor was invited to become an in­structor in the Department of the History of Art; this was the first university-level appointment in America of a specialist in the field of Southeast Asian art. In 1971, he was appointed full professor.

Contrary to the usual stereotype of an art historian, he was an excellent administrator. From 1966 to 1970 he served as chair of the Department of Asian Studies; from 1971 to 1976 he chaired his own department; and from 1979 to 1984 served the Southeast Asia Program as one of its ablest directors.