As an active member of the Intergovernmental Council of the International Hydrological Programme (IHP) of UNESCO, the Netherlands National Commission for UNESCO and the Netherlands National Committee IHP-HWRP organized the workshop ‘Water allocation and green growth’ in cooperation with the Government of the Netherlands. The workshop held in Wageningen in November 2012 served to provide input to the work of the OECD for the coming two years in analysing policy instruments and accompanying measures to facilitate water allocation mechanisms. This publication summarizes the discussions. It is part of a wider series of publications based on several international meetings held in the Netherlands addressing key water issues and challenges. This series reflects the rich expertise of participants from various geographical and disciplinary backgrounds, and thus the true spirit of water cooperation. The hope is that this publication will raise awareness of these sensitive and urgent questions to ensure that ecological principles, including hydrology, are at the heart of economic development and decision-making.