Coastal zones are critical regions, accommodating a significant proportion of the global population and hosting diverse ecosystems that provide essential services. Coastal “Blue carbon” ecosystems, such as mangroves, seagrasses, and salt marshes, play a crucial role in carbon sequestration and storage, biodiversity and coastal protection. Despite their socio-economic and biological importance, they face numerous threats from human activities and climate change, necessitating their conservation and management. Mapping, modelling and monitoring coastal zones using Earth Observation (EO) data is essential for this task. It needs to consider the complex coastal dynamics, past and future change scenarios, and the interaction between Blue Carbon and the coastal zone dynamics. By integrating EO data, advanced modelling techniques, and detailed process-based morphodynamic models, COASTS aims to develop a downstream service for coastal observation, with a focus on Blue Carbon. This service, utilizing Copernicus Marine and other initiatives, will provide govern. stakeholders and coastal planning with relevant information for developing coastal management strategies, including the assessment of blue carbon habitats and their environmental services. Further, COASTS will develop innovative methods and comprehensive analyses to create new business models related to emergent blue carbon markets and will offer new international income sources for countries with blue carbon ecosystem presence. COASTS will initially focus on pilot sites in Germany, Jersey, and the Maldives where govern. customers have a demand and support the project. The learnings from these examples will form a blueprint for broader application in other regions in response to a growing global need. Supported by an interdisciplinary team and strong links with governmental institutions, the COASTS project presents an innovative, scaleable and sustainable approach to coastal conservation and blue carbon management.