The emergence of big data and the data revolution raises a number of governance concerns about the nature and use of data. This chapter describes nine such concerns that an international group of data experts articulated and explored during a series of online discussions devoted to that issue. I then conclude the chapter by arguing against a common interpretation of evidence-based policy decisions – namely, the use of data to try to justify or promote public policy proposals – and in favor of a more critical, and self-critical, approach to evidence-based public policy decisions that uses data to criticize policy proposals instead of trying to justify them. I also argue that we should pay greater attention to the underlying philosophical beliefs, concerns, goals, values, interests, and priorities that motivate them.