[en] Responding to Member States’ requests to physically monitor and report on the types and trends of contaminants in the natural environment is core business for the IAEA Environment Laboratories. This includes providing quality control and capacity building services relevant to radioactive substances and toxic pollutants, as well as communicating how environmental contaminants interact with other stressors to impact biodiversity and undermine the provision of essential ecosystem services. By fulfilling these functions using a practical, hands-on approach, the IAEA Environment Laboratories are unique within the UN system. In this edition of the Environment Laboratories Newsletter, we focus on recent initiatives and field activities to monitor radioactive and other substances in the environment, as well as key partnerships focused on improving the performance of analytical laboratories around the world. We report on a diverse array of activities, from sea water monitoring off the coast of Fukushima, Japan, and the Barents Sea, to training courses on the rapid determination of radioactive strontium in milk and the analysis of trace elements and organic contaminants in marine samples