For most people, face perception is fast and effortless. However, some people without general perceptual or intellectual impairments find face recognition extremely difficult. We have recruited a group of individuals who all have great difficulty recognising even family and friends from their faces. Some of them also have problems with face detection or with recognising emotional facial expressions, while others do not, suggesting that different aspects of face processing depend on different brain mechanisms. To investigate this, EEG (Electroencephalograph) measurements will be taken from individuals with and without face processing problems to obtain event-related brain potentials (ERPs) that are reliable markers of different stages of face processing. Individuals with a specific profile of face processing difficulties should show a distinct atypical pattern of brain responses to faces. This would demonstrate that different face processing problems are linked to distinct stages, which will also be important for our understanding of normal face perception. This project will expand our knowledge of why some people have severe deficits in face recognition, which can have an enormous impact on their social lives. Recent estimates have suggested that up to 2.5 per cent of all people may suffer from this condition.