There is increasing recognition of the important role of teachers in education. But we need to go beyond the idea that teaching is an art that requires exceptional talent. There are exceptional teachers, but we need to support the professional development of all teachers, and we can do so if we invest in the scientific base of the teaching profession and empower those very exceptional teachers to become leaders who inspire other teachers.Technology offers great tools in this respect. I'm thinking of platforms for collaboration in knowledge creation, where teachers can share and enrich teaching materials; of the amount of data that can be collected to measure students' learning; or of the increasing use of blended learning models in teachers' training, in which online lectures are combined with individualized expert support and feedback from peers. Because they enable feedback loops between theory and everyday classroom practice and are supported by a network of like-minded peers, these models have been found to be much more effective than the traditional model of courses, workshops, conferences and seminars