English National Opera (ENO) is a British opera company based in London, resident at the London Coliseum in St Martin's Lane. It is one of the two principal opera companies in London, along with The Royal Opera. ENO's productions are sung in English.

The Royal Opera is a British opera company based in central London, resident at the Royal Opera House in Covent Garden. Along with English National Opera, it is one of the two principal opera companies in London. Founded in 1946 as the Covent Garden Opera Company, the company had that title until 1968. It brought a long annual season and consistent management to a house that had previously hosted short seasons under a series of impresarios. Since its inception, it has shared the Royal Opera House with the dance company now known as The Royal Ballet.