Jean-Baptiste Raina is a marine microbial ecologist working on some of the symbioses and chemically mediated interactions that underpin the health and productivity of the oceans. JB grew up in the South of France and then moved to Townsville (Australia), where he completed his PhD in 2014. He started his career as a postdoctoral researcher at the University of Technology Sydney (UTS) and was then successively awarded a Discovery Early Career Research Award (2015), a UTS Chancellor’s Research Fellowship (2015) and a Future Fellowship (2021). In 2019, JB became deputy team leader of the Ocean Microbiology Group in the Climate Change Cluster at UTS, where he leads the Host-microbe interactions research program. By combining micro-engineering, high-resolution imaging, low-input/high throughput genomics and chemical analyses of microbial communities in situ, JB has pioneered the study of microbial behaviours directly in the marine environment, perfected and applied high-resolution chemical imaging techniques to study previously untraceable microbial interactions in complex systems, and developed novel analytical chemistry methods to quantify chemical cues produced by marine organisms, particularly in the context of coral-bacteria symbioses.