Olivier Ezratty is a freelance quantum engineer, author, trainer, teacher and researcher, mostly known for “Understanding Quantum Technologies”, his comprehensive open-source book on quantum technologies (September 2024, 7th edition, 1,554 pages). He is a teacher and lecturer on quantum and classical technologies at EPITA, CentraleSupelec, Ecole Normale Supérieure Paris-Saclay, and other Universities. He works for a diverse set of government institutions and industry organizations, as a referent expert for Bpifrance, Agence Nationale de Recherche (France) and the European Commission. He is also one of the cofounders of the Quantum Energy Initiative. He has an Msc in Computer Science from CentraleSupelec.