OBJECTIVE To examine whether individuals instructed to fake intellectual impairment on the WAIS-R employed common faking tactics and to assess the accuracy of detection of faking tactics employed. METHODS Two groups of participants were instructed to fake 'mental handicap' on the WAIS-R. The first group included incarcerated young offenders and the second group included postgraduate students and research fellows from a university psychology department. RESULTS Both groups produced faked mean IQ scores within the 'mental retardation' range. There were, however, unusual features in the answers of both groups, including unusual error types. The faking tactics employed were readily detected. CONCLUSIONS The results suggest that an individual's WAIS-R performance should be interpreted with due consideration given to both the quantitative and the qualitative aspects of their presentation.