The DTN-EO study was initiated in order to research the performance of DTN in future missions, particularly Earth observation and constellation-type missions. In the original proposal, ESA stipulated three scenarios which were to be tested: Earth observation, constellation, and exploration missions. These scenarios built upon each other, starting with an Earth observation-centric mission such as the Sentinel missions, before moving to a large constellation. Ultimately, the DTN network from the first two scenarios was expanded to represent a deep-space exploration mission. These three scenarios provided a cross-section of future mission goals and requirements, and were analysed to reveal best practices for missions using DTN.