Warchus has directed for the National Youth Theatre, Bristol Old Vic, Donmar Warehouse, Royal Shakespeare Company, National Theatre, Opera North, West Yorkshire Playhouse, Welsh National Opera, English National Opera in the West End and on Broadway. He won the Globe's Most Promising Newcomer Award for Much Ado About Nothing in the West End, the Evening Standard Best Director award, and Olivier Award nominations for Henry V and Volpone.
Productions include Sejanus his Fall (Edinburgh), "Master Harold"...and the Boys (Bristol Old Vic), The Suicide, Coriolanus (National Youth Theatre), Life is a Dream, Plough and the Stars(West Yorkshire Playhouse), True West, (West Yorkshire Playhouse, Donmar Warehouse, Broadway), Henry V, The Devil is an Ass, Hamlet (RSC), Volpone (RNT), Troilus and Cressida (Opera North), Rake's Progress (Welsh National Opera), Falstaff (Opera North & ENO), and Art (West End and Broadway).
His 1997 productions of Hamlet at the Barbican Theatre and Falstaff at the English National Opera have been nominated for several Olivier Awards including Best Director. Hamlet was also seen at the Brooklyn Academy in New York and the Kennedy Center in Washington, D.C.
Warchus directed Yasmina Reza's plays The Unexpected Man (RSC) and Life x 3 (National Theatre) in London and New York (at, respectively, the Promenade Theatre and Circle in the Square Theatre). In 2000 he directed Sam Shepard's True West starring Philip Seymour Hoffman and John C. Reilly. In 2002 he directed Our House, at the Cambridge Theatre, a new musical written by Tim Firth featuring the music of Madness which won the Olivier Award for Best New Musical.
In 2007 he directed The Lord of the Rings, the stage adaptation of the novel The Lord of the Rings, which played at the Theatre Royal, Drury Lane from May 2007 to July 2008 and which he wrote the music and book for. It was the most expensive stage production ever at the time of its debut. In 2008 he directed David Mamet's Speed-the-Plow, starring Kevin Spacey and Jeff Goldblum and Alan Ayckbourn's trilogy of plays The Norman Conquests at London's The Old Vic, and Boeing Boeing at New York's Broadhurst Theatre for which he received a Tony Award nomination for Best Direction of a Play.
During the 2009 Broadway season, Warchus directed two productions. One was the critically lauded, 2009 Tony Award winner for Best Revival of a Play transfer of his Old Vic production of The Norman Conquests, for which he won the Drama Desk Award for Outstanding Director of a Play. The other was the 2009 Tony Award winner for Best Play, Yasmina Reza's God of Carnage, for which Warchus won the Tony Award for Best Direction of a Play.