In this study we investigated the functioning of a data-team in a secondary school in the Netherlands. A data-team works on a problem that is relevant for the school and uses of all kinds of 'data' that are present in school. Our research questions were twofold: 1) 'what is needed for a datateam to be able to function?' and 2) 'what benefits do participants of the data-team report?'. We used a qualitative approach to answer these questions by analysing the minutes of the meetings of the data-team. Results show that a data-team needs acces to data (!) and that goals for the investigated problem have to be clear. The participation of a line-manager is essential to establish both access to data and setting of clear goals. Participants claim that they have become more critical and they are also proud that they have contributed to (partially) solving the schools' issue.