This document outlines a strategy to guide the operations and workplan development of the newly established Global Environment Monitoring System for the Ocean and Coasts (GEMS Ocean) Programme. The strategy provides direction and sets priorities for the GEMS Ocean Programme. It is considered a living document whose practical implementation depends on active engagement, adequate financial support, and communication, as reflected in regular updates of operational work plans for annual approval. The co-design process to establish a meaningful and fit-for-purpose GEMS Ocean Programme, as the newest monitoring system in the UN Environment Programme’s Science Division, which acts as the convenor of the Programme, officially began in 2021. This collaborative process is both necessary and timely, as scientific, credible, and open data are urgently needed to assess the impacts of climate change, pollution, and extreme events and to sustainably manage the ocean’s valuable resources and ecosystems.