NextGenMobility tackles the disconnection between youth mobility needs and the spatial, social, and institutional structures of urban (transport) systems. In many small and medium-sized European cities, young people are disproportionately affected by long commutes, poorly integrated transport options, and lack of multifunctional public spaces—conditions that contribute to their selective outmigration. The project addresses a critical knowledge gap: the perception of mobility systems by youth, which includes not only physical access but feelings of safety, autonomy, and inclusion. Current planning rarely reflects these subjective dimensions, leading to interventions that miss the mark. NextGenMobility directly engages with this challenge by exploring how to localize the 15-minute city model in diverse urban contexts, ensuring it becomes socially inclusive and youth-relevant. By understanding how young people experience time, space, and movement in their daily lives, the project creates a foundation for mobility planning that is sustainable, equitable, attractive, and responsive to future generations.