Our meeting intends to create a dialogue between observers, modelers and theoreticians to share problems, ideas and methods around stellar multiplicity and interaction. This is only one side of the coin: even if for some research fields stellar multiplicity is a given and well embedded in methods, its importance is controversial in other fields, despite observational and/or theoretical evidence. Our meeting also aims at addressing these controversies by providing a stage for the latest arguments, and a constructive environment for dialogue and fostering scientific collaboration.