Warden made his screen debut in "U.S.S. Hathaway/You're in the Navy Now" (1951), a slight military comedy that marked the debut of two other actors who would also enjoy long screen careers, Lee Marvin and Charles Bronson (here billed as Charles Buchinsky). In many of his other early films, Warden often played hard-boiled military types but he also made his mark as one of a group of urban white collars workers trapped by life in the emotionally affecting "Bachelor Party" (1957) and, as the impatient juror, in the well-remembered courtroom drama "Twelve Angry Men" (both 1957). In Sidney Lumet's directing debut, "Edge of the City" (also 1957), he delivered a gritty performance as a ruthless hiring boss on the New York waterfront.
Warden worked steadily in TV and film throughout the 1960s, 70s and 80s, gradually developing a talent for vulgar comedic roles. Some of the more memorable performances were in "The Man Who Loved Cat Dancing" (1973) as a scruffy outlaw, as the cab-driving pimping father in the Canadian produced comedy "The Apprenticeship of Duddy Kravitz" (1974), as a hard-nosed editor in "All The President's Men" (1976), and as a garment district hustler in "So Fine" (1981). For his supporting work in two Warren Beatty vehicles, "Shampoo" (1975), where he played a philandering husband, and in "Heaven Can Wait" (1978) as a blustering football coach, Warden picked up Oscar nominations.
Warden enjoyed an extensive career on the small screen beginning in TV's "Golden Age". He appeared in countless TV dramas, movies, miniseries and was the star of numerous weekly series beginning with a two- year stint as a regular on "Mr. Peepers". Warden frequently played detectives in series TV, among them, the complex crime solver "Jigsaw John" (1976), a plain clothes veteran in "N.Y.P.D." (1967-69), and a con man turned private investigator in "Crazy Like a Fox" (1984-86). Though Warden often got starring billing in his later work, he remained the quintessential supporting character. Having previously acted in Woody Allen's misfire drama, "September" (1987), Warden showed up as a respected theater producer in Allen's decidedly lighter comedy, "Bullets Over Broadway" (1994).