Uniquely in Europe, state aid policy has been used in the financial crisis to control the flow of public funds to the banking sector. For the next few years, state aid decisions will determine the timetable for aid to be withdrawn and for market principles to be restored. What lessons does the crisis provide for future state aid policy in banking? Can policy-makers put competition first? Can they take a tough approach without provoking a further crisis? And how should the difficult economic trade-offs be managed?