With a name that literally means 'The Party of Wales' and a blossoming membership of around eight thousand, Plaid Cymru is the prominent political voice in favour of an independent Wales.
As well as campaigning for the country's full withdrawal from the United Kingdom, the party also advocates more teaching and speaking of the Welsh language and the promotion of both traditional and modern Welsh cultural values.
The party came to prominence in 1999 after an eventful and rather bad-tempered local election battle that involved Labour's candidate for first minister (the Welsh equivalent of PM) standing down following a sex scandal, thereby handing much of the Labour vote to their opponents in Plaid Cymru.
On a national level (the UK that is), Plaid Cymru have become a relatively successful force in politics, but it is in Wales that they wield real power - they registered nearly 15% of the Welsh vote in the last election.
With small numbers of seats in both Westminster and Brussels, Plaid Cymru have found it necessary to form coalitions with other small, like-minded parties in order to exercise more influence.
The most long-lasting and valued of these links is that to the Scottish Nationalists, with whom Plaid Cymru often vote as a single bloc on important issues, especially in the European Parliament.