NESTS was a 4-month ESA FLPP study with the goal of investigating defined preliminary elements for future space transportation solutions to be used in 2030—2050. In this project, eSpace’s goal was to contribute value to the NESTS project and ESA’s efforts to plan future European space transportation; to strengthen collaboration with ArianeGroup; to gain capability in practical future planning criteria and trade-offs. eSpace’s role in this fast-paced project was to establish the method and criteria that would be used to assess the different space transportation services and system concepts, including criteria and weighting factors; to contribute to the elaboration of high-level specifications related to on-orbit servicing, constellation deployment, and Moon missions; and to manage the trade-offs to be performed on space transportation services, including through online workshops.