The First Mutual Learning Lab (MLL1) of the POW-BRIDGE project took place in Slovenia (online format via ZOOM) on 24 November 2020. It aimed to detail the problems in the enactment of posting legislation and to improve our understanding of the challenges that arise from the gap between procedures (legal basis) and practices (experiences) in the posting of workers. The MLL1 gathered 30 participants representing employer associations/chambers of commerce, trade unions and public authorities from the eight participating countries. Participants exchanged their know-how and shared their views on the five main topics/themes based on information collected during our research on posting.