Attended Chaminade High School

Father of two adopted children: Cormack (b. 1993) and Sarah (b. 1995).

While performing "Death Of A Salesman" and "Long Day's Journey into Night" on Broadway, so many of his fans wanted to meet him after his performances that show producers had to hire extra security to keep the crowds in control near the stage door.

Has won two Tony Awards as Best Actor (Play) on his only two nominations: in 1999 for a revival of Arthur Miller's "Death of a Salesman," and in 2003 for a revival of Eugene O'Neill's "Long Day's Journey into Night."

Daughter is actress Elizabeth Dennehy.

Three performances of Dennehy's Broadway play "Death Of A Salesman" had to be cancelled because he had been unable to sleep and generally didn't feel well. After a check-up in the hospital, he was diagnosed with hypertension. [14 March 1999]

Father of Kathleen Dennehy.

Graduated with a B.F.A. in Theatre / Performing Arts from Columbia University, New York.

Began his stage acting career performing in both summer stock and Off-Broadway productions.

Loves sailing.

Owns a home in Santa Fe, New Mexico and a little cottage in Ireland.

His younger brother is an FBI agent.

Appears in both Presumed Innocent and its made-for-television sequel, The Burden of Proof. He is the only actor to appear in both films, and plays a different role in each.

Has stated that On the Waterfront (1954) is his favorite movie.

Joked on the Tonight Show that he is often mistaken for Charles Durning.

Lives in Woodstock, Connecticut. [2008]

Member of the Sigma Chi Fraternity.

Attended Columbia University.

Daughter is actress Elizabeth Dennehy and Kathleen Dennehy.

Dennehy served in the United States Marine Corps. But contrary to previous press releases he never saw any combat nor was he wounded.

Used to work as a stockbroker at the same firm as Martha Stewart. The two remain good friends.