For over 40 years ESA’s Earthnet Programme has played a significant role as part of ESA’s mandatory activities, being a major contributor to the Global Earth Observation System of Systems (GEOSS). This role involved providing the framework for integrating non-ESA missions, i.e. Third Party Missions (TPM), into the overall ESA Earth Observation (EO) strategy. Complementary to ESA-owned EO missions, the programme allows European users access to a large portfolio of TPM and is particularly important for promoting the international use of EO data.<p> </p>In line with the Earthnet Programme objectives first established in 1977, ESA aims to foster cooperation and collaboration with not only other national space agencies, but also commercial mission providers. In recent years the availability of low cost small satellites and the innovation of constellations resulted in an increased number of commercial companies who have established business models to provide information services fed by their own satellite systems. These New Space players are now portraying an important role in the EO international strategy. Some of these new missions are potential candidates for Earthnet TPMs, and ESA have therefore set up a project to assess the quality and the suitability of these missions and also to establish dialogues with the various mission providers in order to improve the overall coherence of the EO system. This project is known as the Earthnet Data Assessment Pilot (EDAP).<p> </p>The EDAP consortium, headed by Telespazio VEGA UK is aimed at the provision of various clusters of expertise to perform an early data quality assessment of existing or future EO missions from national or commercial providers, which may potentially become TPMs within ESA’s Earthnet Programme. Complementary to this support is a focus on the generation of methodologies and guidelines for training and capacity building with each mission provider in regards to performing efficient data quality assessments in preparation for future missions.<p> </p>This work presents how the EDAP activities are organized and executed, and will also provide details of the various missions included within each of the instrument-specific domains covering Optical Sensors, Synthetic Aperture Radar (SAR) and Atmospheric missions. Important multi-mission aspects will also be presented for studies that will require inputs from several missions, possibly spanning multiple instrument domains; such studies contribute to interoperability across existing and future missions and help foster synergies between these missions.