In this study co-creation, defined as a tourist's subjectively lived on-site experience involving actively participation and interaction, is found to enhance attention, involvement, and memorability. A conceptual model of on-site co-creation is proposed and empirically tested in the context of two experiences with dolphins in a marine life park. Results were analysed using SEM and reveal that co-creation significantly influences attention and involvement and also that the higher levels of attention and involvement generated are associated with memorability.