Autism affects 1.1% of the adult population. High-functioning individuals with autism, Asperger’s syndrome, may remain undiagnosed until adulthood. Autism is a life-long condition characterised by problems in two core dimensions: difficulties with social communication and strongly repetitive behaviour, resistance to change or restricted interests. The history should identify early developmental and behavioural problems in different settings e.g. at home, in education or employment. Sensory and GI problems are very common, and should be asked about. The Autism-Spectrum Quotient (AQ-10) is a 10-item questionnaire for people with suspected autism. It provides a time-efficient, structured way of ascertaining key symptoms and clearly signals those who should be referred for further assessment.