In recent years, many countries have started to draft strategies and policies related to the data economy. To support new data- driven activities and innovations, the development of a national data infrastructure (NDI) is seen as key. The concept of NDI has entered governmental strategic discussions on data as an asset, the role of data infrastructures in innovation and economic activity, and the role of government therein. However, there is a gap between the ambitions as laid out in the strategies and the actual actions taken towards realizing them. To understand this gap and support NDI development, insight is needed in the components and processes of realizing NDI strategies. In this paper, we study NDI strategies ‘in action’ in the Netherlands and Switzerland using an analytical framework comprising strategies, stakeholders, design, components and governance. Special emphasis is put on the role of government in formulating and implementing strategies. Our cross-case analysis uncovers lessons that seem relevant for NDI development elsewhere, as well as challenges that need to be resolved before NDIs can hope to actually make the impact associated with them.