As the editors of this special issue, we are delighted to introduce a selection of recent achievements associated with the French Research Network Groupement de Recherche) on Fundamental and Applied Microgravity (GdR CNES/CNRS 2799). Last year marked the 30th anniversary of this group, making it the longest-standing GdR accredited by the Centre National de la Recherche Scientifique (CNRS). To open the 4th decade of our group, the Comptes-Rendus Mécanique de l’Académie des Sciences offered the invigorating opportunity of this special issue.