Jérôme Harlay attended a technical meeting on best practices for Ocean Acidification (OA) experiments in multi‐stressor scenarios. The meeting was hosted by the International Atomic Energy Agency (IAEA) of the United Nations (UN) in Monaco from 24 – 28 June 2019. The purpose of the workshop was to develop and apply new methods and best practices for OA studies in a multi-stressor context including pH, temperature, hypoxia and eutrophication. The knowledge acquired will help identify research questions related to OA research and to also develop an experimental approach to test the response of crustal coralline algae in a multi stressor approach that relates to coastal eutrophication, global warming and OA.. It is worth noting that the Western Indian Ocean Marine Science Association (WIOMSA) is part-financing an OA research project in BERI.