Marianne Elliott has left the National Theatre  after a decade as an associate director to form her own production company.
Elliott is launching the new theatre company with NT producer Chris Harper. Full details of the company, and the productions it will stage, have yet to be announced.
NT director Rufus Norris  praised Elliott’s “immense contribution to the NT” as a director and an associate.
He cited outstanding productions including Saint Joan  and Husbands and Sons . Elliott is also the director of the hugely successful productions of War Horse  and The Curious Incident of the Dog in the Night-Time , which Norris said “have transformed our understanding of what theatre can be, and have helped to cement British theatre’s reputation internationally”.
He added: “We’re thrilled that our relationship with Marianne will continue, not least with Angels in America opening next year.”
Elliott’s first show at the NT was Ibsen’s Pillars of the Community,  which she worked on as a visiting director. Following that, she was asked to work at the venue as an associate, taking up the position in 2006.
In 2013, Elliott ruled herself out of the running to replace Nicholas Hytner  as director of the NT, claiming it would be “particularly difficult” as a mother.
She previously held the post of artistic director of Manchester’s Royal Exchange .