The European Union project, Erasmus Mundus External Cooperation Window, has been implemented since 2010 at MUST. In the sphere of this project, roughly 50 lecturers and students of MUST studied and did research in Austria, Germany, France, Spain, Hungary, Italy, and Finland. In addition, lecturers and students arrived at MUST from Italy, Germany, and Bulgaria. Katya Dishlieva and Sashka Petkova, lecturers at the Technical University and the University of Chemical Technology in Sofia, Bulgaria worked at the School of Humanities Sciences in September 2015 and exchanged experiences in mathematics teaching in foreign languages. Besides, a cooperation contract between the Technical University of Sofia and MUST was established. The aim of this contract lies in developing collaboration in exchanging lecturers, students and research students among MUST, the Technical University of Sofia, and the University of Chemical Technology of Sofia in the future.