The Libergier High School in Reims is a city-center secondary school that welcomes both high school students and higher education students, from the second year of secondary school up to the BTS (Advanced Technician's Certificate). In addition to its participation in the Erasmus+ program through KA131 projects, the school holds the ECHE charter, which supports and promotes the mobility of both BTS students and staff. The BTS in International Trade is the only program that requires students to complete a minimum two-month internship abroad. It serves as a driving force for the other BTS programs, encouraging as many students as possible to undertake an internship abroad. Staff working in BTS programs are also encouraged to take part in training mobilities to strengthen partnerships with intermediary organizations such as European schools or directly with host companies. The aim of this project was therefore to extend its impact beyond just the BTS in International Trade. Indeed, the KA131 project at Libergier High School in Reims aims primarily to promote European and international openness, in line with the school’s institutional goals and to give life to the Euróscol label it has earned. The project addresses identified needs in the development of linguistic, professional, and sociocultural skills. The project team—composed of the head of school, their deputy, the DDFPT (Director of Vocational Training), and the ERAEI (International Mobility Coordinator)—seized the opportunities offered by the KA131 action of the Erasmus+ Program to provide mobility opportunities for participants, while ensuring the principles of equity, transparency, and inclusion. There are three main types of mobility activities: Internship mobility within Europe and internationally for most International Trade BTS students (since the internship abroad is mandatory in this program), Hybrid mobility for a few voluntary students, organized thanks to strong, long-standing partnerships, Training mobility for staff, aimed at enriching their professional practices in relation to local, national, and European contexts. Surrounding these mobilities, the project team made sure to build a network of reliable actors, such as foreign companies hosting interns, partner European schools, and local organizations like regional French companies and local mobility support institutions such as the Région Grand Est, the French Foreign Trade Advisors (CCEF), and the Regional Youth Information Center (CRIJ).