This paper aims to contribute to the ongoing and future debate about the relationships between Big Data, official statistics and development. This paper argues that Big Data needs to be seen as an entirely new ecosystem comprising new data, new tools and methods, and new actors motivated by their own incentives. The emergence of this new ecosystem provides both a historical opportunity, and a political and democratic obligation for official statistical systems to recall, retain or regain their primary role as the legitimate custodian of knowledge and creator of a deliberative public space for and about societies.