Plaid Cymru (Welsh pronunciation: [ˈplaɪd ˈkəmrɨ], English: The Party of Wales; often referred to simply as Plaid) is a political party in Wales. It advocates the establishment of an independent Welsh state.

Plaid Cymru was formed in 1925 and won its first seat in 1966. Plaid Cymru by 2012 had 1 of 4 Welsh seats in the European Parliament, 3 of 40 Welsh seats in the Parliament of the United Kingdom, 11 of 60 seats in the National Assembly for Wales, and 206 of 1,264 principal local authority councillors.

Plaid Cymru's goals as set out in its constitution are:

In September 2008, a senior Plaid Cymru assembly member spelled out her party's continuing support for an independent Wales. The Welsh Minister for Rural Affairs, Elin Jones, kicked off Plaid's annual conference by pledging to uphold the goal of making Wales a European Union member state. She told the delegates in Aberystwyth that the party would continue its commitment to independence under the coalition with Labour.

While both the Labour and Liberal parties of the early 20th century had accommodated demands for Welsh home rule, no political party existed for the purpose of establishing a Welsh government. Plaid Genedlaethol Cymru (English: National Party of Wales) was formed on 5 August 1925, by Moses Gruffydd, Fred Jones and Lewis Valentine, members of Byddin Ymreolwyr Cymru (Home Rule Army of Wales; literally, Self-Rulers' Army of Wales); and H. R. Jones, Saunders Lewis and David John Williams of Y Mudiad Cymreig (The Welsh Movement). Initially, home rule for Wales was not an explicit aim of the new movement; keeping Wales Welsh-speaking took primacy, with the aim of making Welsh the only official language of Wales.

Leanne Wood AM (born 13 December 1971), is a Welsh politician and the leader of Plaid Cymru. She was born in the Rhondda, Wales, and has represented the South Wales Central region for Plaid Cymru as a Member of the National Assembly for Wales since 2003, and was elected leader of Plaid Cymru on 15 March 2012. Wood, a Welsh language learner, is known as a republican and socialist.

Leanne Wood was born in Llwynypia on 13 December 1971. She grew up in the nearby Rhondda village of Penygraig, where she attended Tonypandy Comprehensive School (now Tonypandy Community College).

From 1997 to 2000, Wood worked with the Mid Glamorgan Probation Service as a probation officer. From 1998 to 2000 she was co-Chair of the National Association of Probation Officers. Wood worked as a support worker for Cwm Cynon Women's Aid from 2001 to 2002, where she has been Chair since 2001. Wood lectured in social work at Cardiff University from 2000, until her election to the National Assembly for Wales in 2003.

Wood was a councillor on Rhondda Cynon Taf County Borough Council from 1995 to 1999. After leaving the probation service in 2000, she was Jill Evans MEP's political researcher until 2001. Wood was Chair of Cardiff Stop the War Coalition from 2003 to 2004.