His Broadway appearances include A Day in Hollywood / A Night in the Ukraine for which he received a Tony Award nomination,[5] Wicked, The Visit[6], Titanic, Torch Song Trilogy, The Pirates of Penzance, Bells Are Ringing, A History of the American Film[7], and The Great Society.

[8], for which he received a Drama Desk Award nomination, Dead Poets Society[9], Middletown[10], New Jerusalem[11], Geniuses[12], It’s Only a Play[13], By the Way Meet Vera Stark,[14][15] The Cradle Will Rock, and Silence!

I Do!,[21] and On the Town,[22] his many recordings include Songs of New York[23], Show Boat[24], Kiss Me Kate[25], Annie Get Your Gun[26], Of Thee I Sing/Let ’Em Eat Cake[27], Girl Crazy[28], You Never Know[29], Tell Me More[30], Oh!

[32] In regional theatre, he has played the Devil in Randy Newman's Faust (La Jolla/Goodman),[33] Henry Carr in Travesties (Williamstown),[34] Frosch in Die Fledermaus (Santa Fe Opera), Pangloss in Candide (Glimmerglass),[35] Gaston in You Never Know (Pasadena Playhouse),[36] Fagin in Oliver (Paper Mill Playhouse),[37][38] Leonardo da Vinci in Ever After (Alliance Theatre), and Charley in the Arena Stage revival of Merrily We Roll Along[39] for which he received a Helen Hayes Award.

[40] In London, he starred with Tyne Daly, Frederica Von Stade, Kurt Ollmann, and Thomas Hampson in a concert presentation of On the Town, which was broadcast on Great Performances for PBS.

[43] In 1987, Garrison landed his best-known role, portraying Steve Rhoades, next-door neighbor to the Bundy family on the popular sitcom Married... with Children.

[46] Other television credits include Unbreakable Kimmy Schmidt[47], Madam Secretary[48], The West Wing, 30 Rock,[49][50] Law & Order,[51] The Practice, Without a Trace, Everybody Loves Raymond, NYPD Blue, Judging Amy, Murphy Brown, Murder, She Wrote, L.A. Law, Tom Clancy's Op-Center,[52] The Good Wife[53] and, for PBS Great Performances, On the Town with the London Symphony Orchestra and Ira Gershwin at 100: A Celebration at Carnegie Hall.