Background: Concerns about the pharmacological management of the behaviour of individuals with intellectual disability have resulted in the development of legislative and procedural controls. Method: This Australian study provided a comparison of 873 reported cases where drugs were administered to manage behaviour in March 2000, with 762 cases reported in March 1993. Drug use in individuals who remained medicated across time (n = 316: recurrent sample) was also compared with those who were reported only in 1993 (n = 329: limited sample). Results: A small decrease in the proportion of individuals who were reported to have received medication was evident over time (from 5% to 4.5% of total population). However, this was accompanied by an increase in drug diversity and interclass polypharmacy. An increase in antidepressant use was evident (from 7.4% to 13.8% of reported drugs), and there was a trend towards greater reporting of medication for acute behavioural problems and medication use with children. Greater use of antipsychotic drugs was evident in individuals who remained medicated across time compared with those who did not. Conclusions: The findings suggest the need for continuous research into practice. The fact that many individuals receive medication over long periods makes it incumbent on service providers to engage in regular, comprehensive and individualized review and evaluation of medication regimes.