Approaching regionalism - where this refers to subnational territorially-based social, political and economic phenomena - from what might be termed an 'international relations' perspective prompts several questions. Firstly, why should one engage in such an exercise? After all, is not regionalism, in its various definitions, perceived in terms of domestic rather than international politics? The answer to this, as to similar propositions regarding the analysis of human affairs in an increasingly inter-linked world, is that our traditional disciplinary boundaries no longer accord with the structures and processes which they seek to describe. This is particularly so where the boundaries separating what have been regarded as discrete arenas of political activity are concerned. It is not so much that 'international relations' can provide startling new perspectives on this issue. Rather, its characteristic preoccupations with the nature of the international system and the patterns of interaction within it have become increasingly intermeshed with those on the 'domestic' side of the disciplinary divide and are therefore essential to an understanding of them. If this appears to be evasive, then it reflects the fact that the author has spent much effort in teaching and research arguing that our understanding of political processes require a relaxation of the international-domestic divide (Hocking and Smith, 1990; Hocking 1993).