The AQ (Autism-Spectrum Quotient) is a self-administered instrument for measuring the degree to which an adult with normal intelligence has the traits associated with the autistic spectrum. The AQ was administered in Japan to test whether the UK results would generalize to a very different culture. Three groups of subjects, adults with AS or HFA (n=57), adult controls (n=194), and University students (n=1050) were assessed. The adults with AS/HFA had a mean AQ score which was significantly higher than both the controls and the University students. Among the controls, males scored significantly higher than females. The similarity of results in both the general population and the clinical group across the two cultures was remarkable.