Over six feet tall, with wild eyes, a high forehead, unkempt hair and frequently a beard, Mr. Libertini made an immediate impression upon entering a scene. Owing to his appearance, he often played eccentric characters, or establishment figures (detectives, priests, rabbis, etc.) with an eccentric edge, and embodied a wide variety of ethnicities, from Jewish to Italian to Hispanic.

Among his best known film roles were the crazy Latin-American dictator in the comedy "The In-Laws" (1979), Chevy Chase’s exasperated editor in "Fletch" (1985), a vaudevillian in Terrence Malick’s "Days of Heaven" (1978) and spiritual advisor Prahka Lasa in Steve Martin's "All of Me."

In Woody Allen’s comedy about a tourist nightmare, "Don’t Drink the Water," he played Father Drobney, repeating a role he had created on the Broadway stage in 1966. The hit play was Mr. Libertini’s Broadway debut. He would return to Broadway in Paul Sills’ Story Theatre, Ovid’s Metamorphoses, Bad Habits, Conversations With My Father and Sly Fox.

His Off-Broadway credits included Plays for Bleecker Street, 3 x 3, The Cat’s Pajamas, The White House Murder Case, The Primary English Class, Love’s Labor's Lost, As You Like It and Hamlet, in which he played Polonius opposite Liev Schreiber’s Hamlet. The latter three were all with the Public Theater.

On television, he played a Godfather on the satiric comedy "Soap," was a detective on "Pacific Station" and a priest on "The Fanelli Boys." He was born May 21, 1933, in Cambridge, MA, into an Italian family who had emigrated from southern Italy. He graduated from Emerson College in Boston. After moving to New York he teamed up with two former college classmates to create, in 1960, an Off-Broadway revue called Stewed Prunes. The show was a success. It ran the better part of a year in New York and then toured.

In 1966, he appeared in another Off-Broadway revue that made an impact, The Mad Show, derived from Mad magazine, and with music by Mary Rodgers. The talented cast featured future stars Jo Anne Worley, Linda Lavin and Paul Sand. It ran nearly two years. (Today, the show is best known for having included Rodgers and Stephen Sondheim’s parody number "The Boy From...").

A marriage to actress Melinda Dillon produced one child, Richard, who survives him. The marriage ended in divorce in 1978.