Water governance strongly depends on the institutional arrangements in place. The plethora of recent inquiries into the adequacy and integrity of governance arrangements in the Murray Darling Basin (MDB) indicates a crisis of trust, legitimacy and public confidence–in short, a loss of authority. With the prospect that current arrangements are losing the authority and legitimacy needed to govern the Basin, pressure is mounting for further reforms due to scandals exposed in the media throughout 2017 and 2018. These and subsequent inquiries have revealed serious concerns about probity, integrity, maladministration and the adequacy of compliance and enforcement regimes. The productive potential of this crisis is that draws attention to the need for reforms to governance institutions. This paper aims to explore the redesign of the institutional architecture in the MDB. Given the profound challenges of social and climate change that are demanding reconsideration of the underlying models used in adaptively governing large complex socio-ecological systems, the paper asks what arrangements are suited to the challenges of governing the Basin in the 21 st century? This paper explores the nature of the redesign challenge, exploring principles, practices and features of MDB governance. The need for institutions with capacity for strategic navigation, goal seeking and the cultural co-construction of authority are suggested in the interests of cultivating debate about prospective reorganisation.