Over the past two decades, Luxembourg has seen a significant increase in the number of cross-border workers, leading to unprecedented saturation of transport networks. To help decision-makers solve this problem, the Agence d'urbanisme Lorraine Nord (Agape) launched the MMUST project, bringing together Belgian, French and Luxembourg partners to improve travel forecasts. From 2018 to 2022, a comprehensive travel model was developed using various mobility surveys carried out independently between 2012 and 2017. Despite modeling and harmonization efforts, this survey base showed significant limitations, particularly for short trips and the apprehension of cultural differences. As a result, a new joint mobility survey for France and Luxembourg will begin in autumn 2024. A survey of stated modal choice preferences was also carried out. Combined with conventional data, this has considerably improved the prediction of future mobility patterns.