Jean-Baptiste Raina is a marine microbial ecologist working at the interface of microbiology, chemical ecology and biophysics, aiming to decipher some of the most important inter-species interactions that underpin the health and productivity of the oceans. Born in France, he completed his PhD in Townsville (Australia) in 2014. After a year of postdoctoral research at the University of Technology Sydney (UTS), he secured several fellowships to pursue his own research: a Discovery Early Career Research Award (2015), a UTS Chancellor’s Research Fellowship (2015) and a Future Fellowship (2021). In 2019, Jean-Baptiste 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, he 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. His leadership in microbial ecology was recognised by the 2024 Alma Dal Co Award from the International Society for Microbial Ecology.