It is increasingly common for researchers to rely on the use of data sets that were not originally intended for research purposes. These data sets often lack appropriate documentation and information about how they were created and are often less reliable. The project ‘Building a FAIR Expertise Hub for the social sciences’, which was recently awarded funding by the Platform Digitale Infrastructuur Social Science and Humanities (PDI-SSH), is aimed at targeting this issue by supporting the data providers in the social sciences in improving the Findability, Accessibility, Interoperability and Reusability (FAIRness) of their data.