This article focuses on a key issue for the sustainability of bilingual education: teacher training for content and language integrated learning (CLIL). It begins by canvassing the main innovations affecting teacher training within the current CLIL panorama in terms of the CLIL teacher training profile and the interesting evolution that research into the topic has undergone. The chief challenges stemming from aforementioned innovations are then examined on 7 main fronts: linguistic competence; methodology; scientific knowledge; organizational, interpersonal, and collaborative competence; and ongoing professional development. Finally, 5 concrete lines of action are proposed to address these niches, illustrated with specific practical examples from diverse educational contexts. The updated research evidence and specific actions presented in this article provide a comprehensive overview of where educators stand and where they need to go in the area of teacher training to guarantee a success-prone implementation of CLIL in the European continent and beyond it.