Sir Nicholas Robert Hytner (/ˈhaɪtnər/ HYTE-nər; born 7 May 1956) is an English theatre director, film director, and film producer. He was previously the Artistic Director of London's National Theatre. His major successes as director include Miss Saigon, The History Boys and One Man, Two Guvnors. He is also known for directing films such as The Madness of King George (1994), The Crucible (1996), The History Boys (2006), and The Lady in the Van (2015). Hytner was knighted in the 2010 New Year Honours for services to drama by Queen Elizabeth II.

Hytner was born in the prosperous suburbs of south Manchester in 1956, to barrister Benet Hytner and his wife, Joyce. He is the eldest child of four, and has described his upbringing as being in "a typical Jewish, cultured family".

He attended Manchester Grammar School and went to university at Trinity Hall, Cambridge, where he studied English. He did some acting while at university, including co-scripting and performing in a televised production of the 1977 Cambridge Footlights Revue. However, Hytner did not consider acting his strong point. "I think I was savvy enough when I went to Cambridge to discover I was a poor actor," he said later. He also did some directing, including a production of Bertolt Brecht and Kurt Weill's Rise and Fall of the City of Mahagonny.

After leaving Cambridge, Hytner's first "proper paid job" was as assistant to Colin Graham at English National Opera. Some of his earliest professional directing work was in opera, including at Kent Opera, Wexford Festival Opera and a production of Rienzi at English National Opera. His first theatre productions were at the Northcott Theatre, Exeter. He then directed a series of productions at the Leeds Playhouse, including The Ruling Class by Peter Barnes, an adaptation of Tom Jones and a musical version of Alice in Wonderland. In 1985 he became an Associate Director of the Royal Exchange Theatre, Manchester, a position he retained until 1989.

Hytner was hired by producer Cameron Mackintosh to direct Miss Saigon, the next work from Les Misérables creators Alain Boublil and Claude-Michel Schönberg. "I had seen several of Nick's opera productions – Handel's 'Xerxes' and Mozart's 'Magic Flute' – as well as some of his classical plays, and he has a marvellously visual point of view," Mackintosh said. For Hytner, "It just felt like a huge lark... It was gigantic, and I was into gigantic at the time, so I threw everything I knew at it. It was big, honest, moving, brash, kind of crazy. I had no idea that it would take off."

Hytner's London production of Miss Saigon opened on 20 September 1989, and closed on 30 October 1999 after just over ten years, on its 4,274th performance, having grossed more than £150 million in ticket sales during its London run. Hytner also directed the New York production, where the show recouped its $10.9m investment in 39 weeks. The show, at New York's Broadway Theatre, opened on 11 April 1991 and closed on 28 January 2001 after 4,092 performances.

Hytner was on a percentage for both London and New York productions, allowing him (then aged 34) to never need worry about money again. "It was a huge– a massive stroke of fortune," he said in 2010. "It meant that thereafter I only needed to do what I wanted to do."

What Hytner did was to continue directing theatre and opera, including several productions at London's National Theatre (where he had first directed in 1989 with Ghetto). In 1990, he was appointed an Associate Director of the National by its then-Director Richard Eyre. One of the plays he directed was Alan Bennett's The Madness of George III. When a film adaptation was commissioned, Bennett insisted Hytner should direct it, and the retitled The Madness of King George (1994) became Hytner's film debut.