The European Multidisciplinary Seafloor and water column Observatory (EMSO) participated by 8 Member States (Italy, Spain, Portugal, France, Ireland, Norway, Greece, and Romania) is a unique marine multidisciplinary, distributed Research Infrastructure, with the goal to explore, monitor and better understand the phenomena happening within and below the oceans and their critical impact on the Earth. Inserted in the European Strategy Forum on Research Infrastructures (ESFRI) Roadmap in 2006, in 2016 EMSO has the status of European Research Infrastructure Consortium (ERIC) by the European Commission. EMSO brings together diverse and numerous scientific partners, Institutes and Research Centres operating in key sites in European seas, from North East to the Atlantic, through the Mediterranean, to the Black Sea, in a common strategic framework of scientific facilities (data, instruments, computing and storage capacity) to promote and drive advances in marine science and technology while enabling access to its services, facilities and technology platforms. EMSO research infrastructure provides relevant information for defining environmental policies based on scientific data, covering a wide range of interdisciplinary areas including biology, geology, chemistry, physics, engineering and computer science, from polar to tropical environments, down to the abyss. Through the valuable contribution of its 14 observatory and test sites, equipped with multiple sensors, placed along the water column and on the seafloor that constantly measure different biogeochemical and physical parameters, EMSO delivers and offers data and services to a large and diverse group of users, from scientists and industries to institutions and policy makers, to better address global challenges, such as climate trends, marine ecosystem preservation, and marine geo-hazards generation and mitigation. EMSO achieved in 2021 the Certification of Compliance to ISO 9001:2015 standard for the “Design, coordination, and development of environmental research activities on seafloor and water-column” and since 2024 has been deploying the ISO 14001, the internationally recognized standard for Environmental Management Systems (EMS).