Benjamin Britten wrote several works in this category in the 1940s when the English Opera Group needed works that could easily be taken on tour and performed in a variety of small performance spaces. The Rape of Lucretia was the first example of the genre, and Britten followed it with Albert Herring, The Turn of the Screw and Curlew River. Other composers, including Hans Werner Henze, Harrison Birtwistle, Thomas Adès, George Benjamin, William Walton, and Philip Glass have written in this genre.
Instrumentation for chamber operas vary: Britten scored The Rape of Lucretia for eight singers with single strings and wind with piano, harp and percussion. Matthew King's The Snow Queen has three singers in multiple roles, with an ensemble of seven players while Judith Weir's King Harald's Saga is for a single soprano voice. The chamber opera Pauline by Tobin Stokes and Margaret Atwood, premiered in 2014 by City Opera of Vancouver, has seven players in the pit (violin, viola, cello, flute/alto flute, clarinet/bass clarinet, bassoon, keyboard), and eight singers for a total of 15 performers.
- Chamber Made Opera, Australian production house