This introduction offers conceptual reflections to frame the special stream on statistical and data literacy in policy-making. It discusses the relevance of the use of statistics and data in politics and highlights their impact on policy-making. It underlines the need for and identifies key meanings of statistical and data literacy in policy-making. It also highlights how statistical and data literacy in policy-making is specific. Finally, it presents the individual contributions to the special stream that originate from the ISI World Statistics Congress 2021 Invited Paper Session on ‘Statistical and Data Literacy in Policy-Making’. The session was co-organised together with the Director of the IASE’s International Statistical Literacy Project (ISLP), Reija Helenius, to whom we are extremely grateful for linking our activities to the ISLP.