Serge Planes has been involved in the study of the genetics of marine fish populations since the beginning of his career, which began with his PhD in 1989. Over the past 20 years, he has published more than 185 articles in international journals dealing with the genetics of coral reef fish populations but also, more generally, with ecology, ecology of marine protected areas and recruitment of marine fish. His early work suggested that connectivity in the marine environment and coral reefs is much more restricted in space than was generally accepted before the 1990s. Most recent work using genetic markers and other techniques has confirmed these early results by demonstrating that self-recruitment in marine populations is a major process to be taken into account in conservation policies. This work has led the international community to consider that marine systems are less dispersive, in contrast to what people believed until the 1990s. More recently, the first application of kinship analysis methods to the marine world has opened the way to new questions about the very evolution of dispersal in marine species. Serge Planes was the director of CRIOBE for 12 years (2007-2018). At the national level, he heads the LabEx “CORAIL”, which brings together all of France’s scientists working on ecology and related issues on coral reefs. Finally, Serge Planes was appointed to the scientific direction of the Tara Pacific expedition, which was launched in May 2016 and lasted more than 2 years across the Pacific Ocean. Tara Pacific is a scientific expedition, but it is also the coordination of a consortium of nearly 20 researchers from more than 8 different organizations that represents a real scientific and organizational challenge.