This special issue of Plasmid features a collection of articles that were presented at the biennial scientific meeting of the International Society for Plasmid Biology, which was held at the University of Toulouse, France, on September 18-22, 2022. The conference was organized by Jean-Yves Bouet and François Cornet, assisted by Daniela Barilla, Fernando de la Cruz, Didier Mazel and Marie-Cécile Ploy. The meeting, which had been postponed twice due to the Covid-19 worldwide pandemics, was attended by over 200 plasmid biologists from 21 different countries.