Abstract
Developing the “Science of Science Policy” will require data collection and analysis related to the processes of innovation and technological change, and the effects of government policy on those processes. There has been much work on these topics in the last three decades, but there remain difficult problems of finding proxies for subtle concepts, endogeneity, distinguishing private and social returns, untangling cumulative effects, measuring the impact of government programs in a true “but for” sense, and sorting out national and global effects. I offer observations on how to think about these issues.