The International Seminar on Sustainable Technology Innovation is a course offered in the framework of the master of Sustainability of the UPC-Barcelona Tech University and financed by the ERASMUS Intensive Program scheme. It introduces backcasting scenarios methodology in real sustainability problems. The learning environment is international, transdisciplinary, intergenerational and intercultural. It includes stakeholders’ dialogues and discussions. The course is organized around current sustainability relevant topics that are analysed in study cases based in different contexts: going from developed to developing countries and from local to global cases. Students apply scenario methodologies to the study cases in order to set up the most contextualized sustainable strategies. The course is structured in four phases: first the local situation analysis where students analyse the topic in their own countries/regions; then students are grouped in international multidisciplinary teams and define the state of the art of the case studies; afterwards students, lecturers and stakeholders meet in Barcelona where the course is run for two weeks and finally students analyse their learning experience in terms of competences acquisition. The topics analysed in the course vary each year and are related to relevant sustainability challenges: urban solid waste management; food and drinks packaging waste; overfishing and marine ecosystem degradation; sustainable mobility, agroecology and sustainable community energy systems. In 2014 UPC Barcelona Tech is running the course for the seventh time and so far more than 170 students, 40 lecturers and 60 stakeholders have participated in the course from 39 countries. This paper explains the learning environment and the challenges and lessons learnt when organizing such a course, and the learning results obtained by students.