To support the offering of data resources and services under defined terms and conditions, marketplaces must be established. This building block supports publication of these offerings, management of processes linked to the creation and monitoring of smart contracts (which clearly describe the rights and obligations for data and service usage), and access to data and services. Based on the technical needs, the corresponding backend processes for rating, clearing, and billing can be executed. The building block thereby facilitates dynamic enlargement of data spaces with more stakeholders, data resources, and data-processing/analytics services (such as big-data analysis services, machine learning services, or services based on statistical processing models for different business functions). It should comprise capabilities for publishing data resources following the broadly accepted DCAT (Data Catalogue Vocabulary) standards, and for harvesting data from existing open-data publication platforms.