Some are mainly involved in the production of knowledge, others are more closely tied to firms and industrial innovation, and still others deal with public goods, such as standards, weather forecasting or developing test methods. Ideally, evaluation should help determine the economic effects of public investment in R&D and innovation, such as the contribution to growth, and the social impacts, such as better health outcomes. Moreover, policy makers increasingly want public investment to help meet global challenges, such as energy, security and climate change.