The Smith Commission was announced by Prime Minister David Cameron on 19 September 2014 in the wake of the 'No' vote in the 2014 Scottish independence referendum. The establishment of the commission was part of the process of fulfilling The Vow made by the leaders of the three main unionist parties during the last days of the referendum campaign. The Vow promised the devolution of more powers from the Parliament of the United Kingdom to the Scottish Parliament in the event of a No vote.