Abstract. The GMES and Africa, MarCOSIO project, promotes the sustainable management of marine resources, improves marine governance, and stimulates the growth of the blue economy in the Southern African and Indian ocean region. Because of its mandate, a wide range of applications, and regional view that incorporates eight countries, the MarCOSIO Information Management System adopts and continues to strive towards implementation of open data principles. This paper presents considerations of the MarCOSIO information management systems towards the adoption and implementation of open data, FAIR and TRUST principles, to ensure the sustainability of its services and offerings. The implementation of the system is evaluated against criteria that assess the alignment to FAIR, TRUST, and Open Data principles. An assessment of the results shows that the system aligns closely, though not fully, with the FAIR and TRUST principles. This is mainly due to the use of reputable open-source tools that implement well-known and accepted standards. On the basis of the services provided, the system cannot be fully open, as in some cases the need for security outweighs the openness. This is specifically true for cases where there is a need to protect personal information, and public disclosures are prohibited by law. The use of open data from the European Commission has allowed the rapid development of regionally relevant solutions that, in turn, have remarkably improved decision making in promoting the protection and growth of the ocean economy. It is one of the goals of the open data directive to increase public participation in the achievement of economic growth.