This introductory paper reviews the literature on the use of evidence-based knowledge (EBK) in the initial and continuing professional development of teachers and also in their everyday practice. It will set the scene for the theme of the SI and critically discuss general current issues about the generation of educational research evidence, how teachers may, or may not, acquire this and, drawing on and updating the outcomes of the previous JET SI (41 (5), 2014), some of the implications of translational research and knowledge mobilisation.