The last few years have seen a revolution in the range of platforms and sensors used for observing the marine environment. From autonomous gliders that can cross ocean basins to robotic systems capable of making in situ molecular measurements of microbes, there has been a step change in our ability to observe our seas and oceans. At the same time the drivers for collecting a wider range of marine data at ever higher spatial and temporal resolution in UK waters are increasing. Firstly, in Europe the Marine Strategy Framework Directive requires national assessments of environmental quality, based on measurements stretching from physics to fish and seabirds and from the ocean surface to the seafloor. Secondly, NERC-funded marine research programmes are exploring how the oceans and shelf seas will respond physically, ecologically and bio-geochemically to climate change and anthropogenic pressures over the coming decades. For example; how water masses cross the shelf break leading to deep ocean-shelf sea coupling and the size and fate of carbon dioxide absorbed by the global oceans and shelf seas. Finally, operational oceanography in support of activities such as marine weather and ocean forecasting, offshore energy production and operations (renewables and oil and gas) and search and rescue, for example, requires data about temperature, salinity, waves, currents and sediment transport. Against this background the UK Department for Environment, Food and Rural Affairs (Defra) are supporting a workshop to identify those technologies that can increase the efficiency and reduce the cost of (UK) marine monitoring over the next 5–10 years.