This literature review focuses on the e-use of video in teacher initial and continuing professional development. There is evidence that video technology used synchronously, and particularly asynchronously, can extend the quantity and quality of classroom observation experience, which in turn supports the development of observation, analysis and reflection in viewers. Theorising on these gains, the authors describe how the linking of theory to practice, the development of pedagogical language and collaborative learning through communities of practice might all be related to video-enhanced teacher education. Claims for gains in codified subject knowledge are less convincing.