Data constitutes a relevant asset for the economy and society. As non-rival goods, data can have multiple uses. The EU has promoted the freedom of movement and the reuse of data. However, nowadays it is mainly a few technological companies that monopolize the gains from data reuse. Common data spaces can contribute to a more equitable distribution of these gains. The European Commission shares this perspective and has proposed the establishment of a European data space based on the creation and integration of common sectoral European data spaces as one of the cornerstones of the European Data Strategy. There are several regulatory, organizational, and technical challenges, as well as challenges related to governance, including ensuring that common European data spaces comply with European values and principles. The DGA and the Data Act intend to respond to these challenges. This chapter will analise the concept of a common data space, the common European data spaces being implemented, and the respective regulatory and governance framework.