Many of the problems that face decision-makers, in both the industrial and policy sectors, are complex and multi-facetted. In the face of these complexities, traditional methods of risk assessmenti are inadequate, and can lead to narrowly-conceived decisions, and major surprises in terms of health (and wider societal) impacts. One way of avoiding these failures is to use more integrated and forward-looking methods of assessment, designed to answer the ‘what happens if …’ question. This paper draws on work undertaken in two current EU-funded projects (INTARESE and HEIMTSA) to show why such methods are needed, what form they might take, how they might fit into an effective cycle of risk governance, and some of the challenges that they pose. Examples will be drawn from a range of current and recent policy areas, including climate change, energy, biofuels and air pollution.