Alpert was best known as the cofounder of the National Society of Film Critics, which he started in his New York City apartment.
[1] Following his departure from the Army, Alpert found employment as an assistant fiction editor for the New York Times from 1950 to 1956.
[1] His freelance work led to his securing a position as a film critic for the Saturday Review,[1] which he held until 1975.
[1] Many joined Alpert's new group in order to counteract the influence of the then New York Times film critic, Bosley Crowther.
[1] According to another founding member, Joe Morgenstern, Alpert "was widely seen as a serious, knowledgeable, dedicated film critic.