His best known work is arguably The Last Sitting, a collection of 2,500 photographs taken of Marilyn Monroe over a three day period, six weeks before her death, taken for Vogue. Stern published Marilyn Monroe: The Complete Last Sitting in 1992. In it, he recounted being enchanted by her until a near-intimate encounter after the second day of shooting; he then realized that she was deeply troubled.
He also directed Jazz on a Summer's Day, a 1959 documentary film set at the 1958 Newport Jazz Festival. In 1999 the film was deemed "culturally significant" by the United States Library of Congress and selected for preservation in the National Film Registry.
Stern worked as a photographer on Lolita and shot the publicity photographs of Sue Lyon. He has photographed Audrey Hepburn, Elizabeth Taylor, Madonna, Kylie Minogue, Drew Barrymore and Lindsay Lohan (recreating The Last Sitting), among others, in addition to his work for advertising and travel publications.