The present competition for coastal and maritime space triggered by human activities, as well as climate change effects and both natural and manmade hazards, impact coastal and marine environment, resources and ecosystems. The physical characteristics, especially the shallowness and its semi-enclosed nature, make the Adriatic and Ionian Sea even more vulnerable to these threats. This situation points out the compelling need in the Adriatic-Ionian Region for a transnational integrated and efficient planning and management of coastal and marine spaces and uses at macroregional level, able to avoid potential conflicts, create synergies and to secure a sustainable growth whilst allowing the preservation of coastal and marine ecosystems for future generations. Such effort requires fit for purpose knowledge and tools. In full compliance with the Integrated Coastal Zone Management (ICZM) and Maritime Spatial Planning (MSP) principles and policies and supporting concretely the implementation of the EUSAIR Action Plan, PORTODIMARE project aims at creating a common platform (Geoportal) for data, information and decision support tools focused on coastal and marine areas of the Adriatic-Ionian Region. The Geoportal integrates and further develops existing databases, portals and tools developed within previous EU projects by local and national administrations and by other initiatives. Through this approach, most of the available knowledge and resources will be efficiently organized and made accessible through a single virtual space, thus supporting coordinated, regionally / transnationally coherent and transparent decision-making processes, with the perspective of remaining operative and being expanded well beyond the project conclusion. The Geoportal will use, feed and support transnational cooperation networks in all the phases of its creation, from the design, to the development, to its testing phase, enabling public authorities and stakeholders to apply a coordinated, integrated and trans-boundary approach. In this view, PORTODIMARE project will test the use of the Geoportal as a concrete support for the development, in four demonstration areas, of strategies and action plans that couple environmental protection and sustainable development of sea/coast uses, within the regional and transnational framework established by Directive 2014/89/EU and EUSAIR Action Plan. More concretely, the PORTODIMARE Geoportal aims at becoming a daily working tool for decision-makers, public and private managers, practitioners, marine scientists and stakeholders in general, thus promoting and boosting sustainable blue growth in the Adriatic and Ionian Region.