Welsh National Opera (WNO) (Welsh: Opera Cenedlaethol Cymru) is an opera company based in Cardiff, Wales; it gave its first performances in 1946. It began as a mainly amateur body and transformed into an all-professional ensemble by 1973. In its early days the company gave a single week's annual season in Cardiff, gradually extending its schedule to become an all-year-round operation, with its own salaried chorus and orchestra. It has been described by The New York Times as "one of the finest operatic ensembles in Europe".
For most of its existence the company lacked a permanent base in Cardiff, but in 2004 it moved into the new Wales Millennium Centre, Cardiff Bay. The company tours nationally and internationally, giving more than 120 performances annually, with a repertoire of eight operas each year, to a combined audience of more than 150,000 people. Its most frequent venues other than Cardiff are Llandudno in Wales and Bristol, Birmingham, Liverpool, Milton Keynes, Oxford, Plymouth, and Southampton in England.