Media and digital literacy are being increasingly recognized as a fundamental competence for teachers of 21st century, but teachers' professional development is still far from coping with this emerging need. This paper aims at providing some recommendations for integrating media literacy into in-service teacher training programs. To this purpose, it will present the results of the experimentation carried out in three European training institutions within the framework of the European project e-MEL (e-Media Education Lab, 2014-17). The overall training process was monitored and evaluated ex-ante, ongoing and ex-post. This paper illustrates and discusses the main findings of the experimentation focusing on strengths and challenges for implementing a teacher training program on digital and media literacy. It concludes with some recommendations and more general reflections on future research directions.