London's main theatre district is located in the heart of the West End of the city centre, and is traditionally defined by The Strand to the south, Oxford Street to the north, Regent Street to the west, and Kingsway to the east although The South Bank Complex is now considered by some to be part of it. Prominent theatre streets include Drury Lane, Shaftesbury Avenue, and The Strand. This area contains approximately forty large theatres and is often referred to as Theatreland. The works staged are predominantly musicals, classic or middle brow plays, and comedy performances.

Most of the theatres in "Theatreland" are late Victorian or Edwardian, and they are privately owned. Most of them have great character, and the largest and best maintained are splendid. On the other hand leg room is often cramped (people were smaller a hundred years ago) and audience facilities such as bars and restrooms are often much smaller than in modern theatres. The protected status of the buildings and their confined urban locations, combined with financial constraints, mean that it is very difficult to make substantial improvements to the level of comfort offered. In 2004, it was estimated that an investment of £250 million was required for modernisation, and the theatre owners unsuccessfully requested tax concessions to help them meet the costs.

West End shows may run for a varying number of weeks, depending on ticket sales. Musicals tend to have longer runs than dramas. The longest running musical in West End history was Andrew Lloyd Webber's Cats, which closed in 2002 after running for 9,000 performances and 21 years, whilst the longest running current musical is Les Misérables with a run of over 8,500 performances and now in its 21st year. It will overtake Cats as the longest running West End musical of all time on 8 October 2006. Other long-runners include Andrew Lloyd Webber's The Phantom of the Opera standing at 19 years and still ongoing, and Willy Russell's Blood Brothers, currently in its 18th year. However the non-musical Agatha Christie play The Mousetrap is the longest running show in the world, and has been showing since 1953.

Top 10 current long-running shows in London:

The Mousetrap (St Martin's Theatre) - 54th Year
Les Misérables (Queen's Theatre) - 21st Year
The Phantom of the Opera (Her Majesty's Theatre) - 20th Year
Blood Brothers (Phoenix Theatre) - 18th Year
The Woman in Black (Fortune Theatre) - 17th Year
Chicago (Adelphi Theatre) - 9th Year
Mamma Mia! (Prince of Wales Theatre) - 7th Year
Disney's The Lion King (Lyceum Theatre) - 7th Year
Fame - The Musical (Aldwych Theatre) - 5th Year
We Will Rock You (Dominion Theatre) - 4th Yea