The purpose of this article is to assess the desirability and feasibility of any point of convergence between Australia’s formal constitutional arrangements and COAG. Although several commentators have suggested that this must be the logical endpoint to the sub-constitutional reform which is currently in train, there is ambiguity about much of the detail of such an argument. We consider precisely how constitutional recognition of intergovernmental co-operation might look – whether it should be of COAG itself (and what difficulties this might introduce in turn) or whether an appropriately facilitative change can be cast in more generalist terms. Of either option it must be asked to what extent it would properly address the concerns that many have expressed about the place of COAG and IGAs in our political system. Given the obstacles to constitutional change, it must be seriously considered whether many of those concerns could be met through reform remaining at the sub-constitutional level. Additionally, an awareness of what might be risked through formal constitutional recognition of a body that certainly enjoys the benefits of adaptability should not be lost sight of. For the present, the sub-constitutional federal arrangements will undoubtedly continue to change rapidly as governments grapple with shared problems in key policy areas such as health, natural resources and education. Others have concluded that no factor has determined the contours of Australian federalism more than the need for pragmatic solutions to policy problems and that these, rather than any overarching constitutional theory of the federal state, continue to drive reform. Nevertheless, as under-theorized and as reactive as these developments are, they only increase the desirability of formal constitutional amendment which is reflective of the reality of Australian federalism today. This is not merely for show or neatness – but rather to recognize that government is found under the Constitution, not apart from or alongside it. The point at which convergence is to occur between the product of political reform on the one hand and constitutional law on the other is surely contestable. It may be some time off yet. But it continues to be foreshadowed and as the need for it is only likely to grow stronger, it is best to be prepared. This article is our contribution to that effort.