Abstract Until very recently, the western Indian Ocean region and its LMEs were poorly understood. In the last 4–5 years, detailed coastal and offshore observations have revealed a wealth of information on the role of current patterns, ocean–atmosphere interactions, habitat and species distribution, and their impacts on the sustainable livelihoods of dependent communities. This new information provides the countries of the WIO with a baseline from which to measure changes within the ecosystem and to predict the likely impacts on marine resources. Most recently, the countries and their partners (NGOs, IGOs, international and regional scientific bodies, etc.) have started to forge a regional alliance (the Western Indian Ocean Sustainable Ecosystem Alliance, WIOSEA). WIOSEA aims to maintain a long-term ecosystem monitoring programme to detect changes from the baseline; to strengthen skill-sets in the region through focused training programmes; to build stronger capacity for modelling and predicting the effects of change; to translate the scientific conclusions and the outputs of high-resolution models and their predictions into pragmatic adaptive management actions and policy decisions, and conversely, to identify and agree on management and policy needs and translate these into research activities. WIOSEA is exploring and evolving a “Dynamic Management Strategy” that will advise action on the basis of a peer-reviewed weight-of-evidence that adopts the validity of trends in the data in terms of management needs and actions, even in the absence of 95–99% confidence limits. This approach has many advantages both to the scientific community and to the management and decision-making sectors of government.