This paper tackles many of the important issues and discussions taking place in Europe and globally about the future of the public sector and how it can use Information and Communication Technology (ICT) to respond innovatively and effectively to some of the acute societal challenges arising from the financial crisis as well as other deeper rooted global problems. These include inequality, poverty, corruption and migration, as well as climate change, loss of habitat and the ageing society. A conceptual framework for open governance systems enabled by ICT is proposed, drawing on evidence and examples from around the world as well as a critical appraisal of both academic and grey literature. The framework constructs a system of open assets, open services and open engagement, and this is used to move the e-government debate forward from a preoccupation with lean and small governments which ‘do more with less’ to examine the potential for open governance systems to also ‘do more with more’. This is achieved by enabling an open government and open public sector, as part of this open governance system, to ‘do more by leveraging more’ of the existing assets and resources across the whole of society, and not just within the public sector, many of which are unrealised and untapped, so in effect are ‘wasted’. The paper argues that efficiencies and productivity improvements are essential at all levels and across all actors, as is maximising both public and private value, but that they must also be seen at the societal level where trade-offs and interactions are required, and not only at the individual actor level.