Policy solutions have been identified, but not always applied where needed nor implemented effectively. This report analyses eight past water and agriculture policy changes in OECD countries with the aim to identify steps towards adopting and implementing such solutions effectively. Selected reforms are assessed systematically via an institutional change analysis and a cross-cutting comparison of political economy factors. A characterisation of reforms is proposed according to the scope of the reform process, the scope of the reform’s action, and the involvement of governments in the design of reforms and their implementation.