The paper analyses a referendum on Scotland’s independence held on 18 September 2014, in particular within the legislative and political framework of the devolution settlement, implemented across the United Kingdom since 1997. Development of Scottish political separatism under the Scottish National Party and its long-time leader Alex Salmond has led to radical changes in the pattern of politics in Scotland. The pro independence SNP has ruled in Edinburgh since 2007, first through a minority government and then securing an absolute majority at Holyrood. It had consistently pushed for a referendum on independence and, after several months of negotiations, managed to sign on 15 October 2012 the Edinburgh Agreement with the British government. The Agreement paved the way for legislation regarding the referendum, in the form of the Scottish Independence Referendum (Franchise) Act and the Scottish Independence Referendum Act. “Yes” vote on 18 September would undoubtedly have enormous constitutional, political, economic, and social consequences for everyone involved, including the complex issues of Scotland’s EU and NATO membership, the exploitation of massive North Sea oil and gas reserves and retaining the British pound as future Scottish currency. But “No” vote would also mean significant adjustment of the British territorial constitution and considerable changes of Scotland’s relationship with the rest of the UK.