This chapter focuses on direct observation and examination, moving consciously from the traditional interview, question, and answer format, to the observational format. Observing 1:1, with a carer present—for example, does the patient engage, both verbally and non-verbally, or is (s)he aloof, unless directly asked to join in? The Autism Diagnostic Observation Schedule (ADOS) is mentioned with an outline description. The limitations of observation, if comorbidity is present, are pointed out, indicating how comorbidity can be distinguished (and then referring on to Chapter 10). Methods used by psychopathologists in psychiatry to observe signs of autism are also refreshed.