John Slattery, a talented actor, was born and raised in Boston, Massachusetts, to parents of Irish descent. His father, John "Jack" Slattery, was a leather merchant, and his mother, Joan (Mulhern),was a certified public accountant.
John's early career in television began with a role on the 1988 series "The Dirty Dozen." He went on to work steadily, appearing in a range of shows, including "Under Cover," "Homefront," "Maggie," and "Feds." He also had recurring roles on "Will & Grace," "Judging Amy," and "Sex and the City," solidifying his status as a sought-after character actor.
In addition to his television work, John has had a successful and diverse career in theater. He made his debut in the 1989 play "The Lisbon Traviata," which starred Nathan Lane. He has collaborated with playwright Richard Greenberg on several occasions, appearing in "The Extra Man," "Night and Her Stars," and "Three Days of Rain," for which he received critical acclaim for his dual roles as father and son.
John made his Broadway debut in 1993, starring opposite Nathan Lane in Neil Simon's "Laughter on the 23rd Floor." He returned to the stage in 2000, starring in a revival of Harold Pinter's "Betrayal."