This article contends that the study of the history of devolution in the UK and the contemporary academic debate over devolution and the future of the UK should involve greater consideration of Northern Ireland. Specifically, it is suggested that the search for linkages, both in historical and contemporary contexts, between Scotland and Northern Ireland around the theme of devolution and constitutional change contributes significantly to an understanding of the broader issue of the interrelations between the 'Four Nations' of these islands. It is demonstrated that the Northern Ireland example of devolution influenced debate in Scotland in the post Second World War years more than has been appreciated hitherto; and that there is much to be studied in the way both places relate to each other and to the devolution debate today.