A fundamental aim of the program was to discover which perceptual mechanisms enable children and adults to make judgements about faces. Taking face identity recognition as an example, at least two mechanisms are important: holistic and adaptive coding (Engfors, Jeffery, Gignac, & Palermo, 2017). Adaptive coding alters the operation of perceptual systems in response to changes in experience. Adaptation can produce striking perceptual aftereffects, but it can also be very useful. We argued that it updates face norms, which represent average properties of our diet of faces, allowing the visual system to efficiently code the distinctive information that we need to recognise faces. Two lines of evidence highlight the functional role of adaptation in face recognition ability (Rhodes, 2017). First, face adaptation is reduced in a diverse range of clinical populations with impaired face recognition. Second, people who adapt more readily to new faces are better at recognising faces and their expressions. These discoveries raise further important questions, such as whether we can learn to adapt more to faces, and if so, whether this could improve recognition of faces in social and forensic settings.