The Stage recognises Hampstead, Sheffield and Michael Grandage Company
Other awards went to the National Youth Theatre and Southwark Playhouse
The Stage newspaper held its annual New Year party at the Theatre Royal, Drury Lane today, at which it announced the winners of The Stage Awards 2014.
The awards, now in their fourth year – and previously titled The Stage 100 Awards – celebrate performing arts organisations and the teams behind them.
This year's winners included Sheffield Theatres, which was named Regional Theatre of the Year for the second year running, Hampstead Theatre, named London Theatre of the Year, and the Michael Grandage Company, which won Producer of the Year following its inaugural West End season.
Hampstead, which topped a shortlist that also featured the Bush Theatre and Young Vic, was recognised for increasing its audience capacity from 70% in 2010 to 91% last year.
The Unsung Hero award went to the late Andy Collier, a theatre consultant and writer who died at Leicester Square tube station last year.
Alistair Smith, deputy editor of The Stage, said: "It was another really tough year for the judges across all the categories and, really, any of our shortlisted organisations would have made worthy winners, such is the quality of theatre provision across the UK. However, these were the best of the best, and the judging panel would like to congratulate all our winners for everything they've achieved over the last 12 months."
London theatre of the year, sponsored by Haagen Dazs
Regional theatre of the year, sponsored by Audience Systems
Fringe theatre of the year, sponsored by Encore Insure
School of the year, sponsored by Nick Hern Books
National Youth Theatre
Producer of the year, sponsored by Ticketmaster
Michael Grandage Company
Unsung Hero, sponsored by the Association of British Theatre Technicians