Doctor of Pharmacy, Biologist of Hospitals, Intern in Pharmacy, then Associate Professor of Universities (Faculté de Médecine, UGA) and Hospital Practitioner at CHU de Grenoble (Laboratoire de Bactériologie – Hygiène): these activities led me to teach Bacteriology Medical in numerous university and paramedical training courses and to invest in the diagnosis of infectious diseases and the epidemiological surveillance of the hospital environment. My research activities have concerned in particular Pseudomonas aeruginosa, an environmental bacteria and the epidemiology of antibiotic resistance. As for Legionella pneumophila, and legionellosis its clinical translation, they have marked my entire career since their discovery and have allowed me to grasp a new bacterial world. As a member of the Conseil scientifique de l’Agence de l’eau Rhône-Méditerranée, I was able to closely follow the evolution of fundamental and technical knowledge for a microorganism and an infection that is still very topical. In this context, as President of the Comité de Lutte contre les Infections Nosocomiales (CLIN)(CLIN) at the University Hospital of Grenoble, I was confronted almost daily with the fight and prevention of nosocomial legionellosis, one of the institutional priorities.