This Policy Brief succinctly presents the Ecological Observing System of the Adriatic Sea (ECOAdS), aimed at integrating the ecological and oceanographic dimensions within the conservation strategy of the Natura 2000 network, and to propose a way to go for its future development and maintenance. After a definition of marine ecological observatories, we describe the current structure of ECOAdS, its key components and potential relevance in relation to the main European strategies for biodiversity and marine observation for the next decade. Finally, we suggest some actions that could be undertaken for the future development of ECOAdS, targeting possible perspectives in different regional, macro-regional, national and European strategic contexts. This Policy Brief is one of the outcomes of the Interreg Italy-Croatia Project ECOSS (ECological Observing System in the Adriatic Sea: oceanographic observations for biodiversity; https://www.italy-croatia.eu/web/ecoss), which had the main purpose to design and carry out the first steps for the establishment of ECOAdS.