Since September 2010, I.E.S. Juan de Mairena Secondary School is offering Bilingual Teaching in French which has become one of the assets of our school. Since September 2014, it also offers the double qualification Bachibac. From a rigorous evaluation of the bilingual programme, our school detected a few aspects which needed to be improved. Amongst them, it’s important to underline the need to rewrite the Educational Bilingual Project having as a starting point the elaboration of a map of cross-curricular competencies, according to, on the one hand, written levels in the Common European of Reference for Languages, and, on the other hand, academic needs of students who wish to acquire the double “A level” qualification “Bachibac”. In order to acquire the above-mentioned competencies, I.E.S. Juan de Mairena has been offering teachers who take part in the Bilingual programme the opportunity to obtain or widen the necessary knowledge, skills and abilities with the aim to hone the above-mentionned map of cross-curricular competencies. Our team is composed of 16 teachers from different subjects with a C1 level (or above) in French. They teach French and other subjects through the medium of French, following the principals of the CLIL methodology (Content and Language Integrated Learning). The project included six Mobility Activities; four of them with participation in structured courses abroad and two other mobility with a job shadowing/observation period abroad in a partner school or relevant organisation. The Head of Studies for the Bilingual Programme has coordinated and managed the staff mobility with the assistance of the teachers involved in the Programme, during our weekly coordination meeting. Staff Mobility Training took place in CAVILAM-Vichy High School which has the required standard of “Qualité Français Langue Étrangère approved by the C.I.E.P. (Centre Internationale d’Études Pédagogiques) which depends on the French Ministry for Foreign Affairs, Ministry of Education and Ministry of Higher Education and Research. Three of our teachers, with a permanent contract, were able to complete the course “Teaching of a school subject through the medium of French: Non Linguistic Subjects (DNL). Two of the above-mentionned teachers teach Social Sciences through the medium of French and our third teacher teaches Music in French too. A fourth teacher in charge of teaching French completed the training course “Teaching French as a foreign language”. After successful completion of these courses, our teachers have greatly improved their ability to identify linguistic and academic competencies required by their subjects, and to plan didactic units from meso-alternation. They are also more able to adapt their teaching to the levels specified by The Common European Framework of Reference for Languages. Moreover, they are now competent in the preparation of their students in order to pass successfully the DELF and DALF exams. The job shadowing/observation period abroad took place in two different French Schools. The first one took place in Lycée Sainte-Thérèse in Quimper, which has a European Bilingual Programme in Spanish, and the second one took place in Lycée Francisque Sarcey in Dourdan, which also prepares student for the dual diploma Bachibac. The teachers from IES Juan de Mairena School were able to find out about the peculiarities of the French Educational System, they team-taught with their French colleagues and discussed with them bilingual methodologies used in the classroom. Before and after their period abroad, the teachers have kept in touch and shared resources. Thanks to the Staff Mobility and the exchange of good practice with the French Schools, the acquired competencies have been shared with the rest of the teaching staff and other schools with Bilingual Teaching Programmes. Furthermore, the map of cross curricular competencies that we are elaborating is now used as a basis for the implementation of a School Linguistic Project which involves all subjects and improves teaching standards and results obtained by I.E.S. Juan de Mairena students, especially when it comes down to their linguistic competence in Spanish as well as in Foreign Modern Languages.