Coastal & Marine Systems are the most dynamic on Earth. They are fluid and are continuously shaped by natural processes and human intervention and, as a consequence, are very complex systems to interpret, understand and manage. They support, as yet, an unknown number of organisms, are a source of vast biological, mineral, food and energy resources and provide a conduit for international trade. The majority of the world’s population lives on the coast and, in addition to housing, it supports significant infrastructure for industry, tourism and transport. Our marine and coastal environments also provide a range of other ecosystems services such as regulation of climate; cultural uses and supporting services like biodiversity and habitats. These interconnected systems are, therefore, hugely important economically, socially and environmentally and the Coastal & Marine Systems Thematic Group has significant experience in conducting research in, and synergising outputs from, these fields. The Group develop integrated solutions and conduct internationally and nationally funded research and consultancy in a broad range of projects and initiatives. This is achieved through the combination of fundamental and applied science across a number of key disciplines including governance, oceanography, ecology and geoscience. Outcomes and outputs are routinely used to advance scientific knowledge and improve understanding of system functioning, inform and enhance management and sustainable development of marine and coastal resources with specific reference to public acceptance, and law and policy frameworks.