The Drug Use Monitoring Australia project (DUMA) continues to provide valuable information on illicit drug use trends among police detainees and insights into illicit drug markets. This bulletin draws upon data from a sample of police detainees from two Local Area Commands within Sydney, collected over the first two years of DUMA’s operation in New South Wales. Both self-report data and urinalysis results were examined. The DUMA results continue to show a high prevalence of illicit drug use among police detainees, with over 70 per cent of the sample indicating illicit drug use in the past 12 months and half of the sample indicating recent use of at least one illicit drug. An examination of urinalysis results over the two-year period provides evidence of a decline in the use of heroin in the first half of 2001 and an increase in cocaine use over the same period. Self-report data on illicit drug transactions suggest that purchasing practices vary according to type of drug being purchased. Purchases of heroin and cocaine were more likely to be conducted in public and occur outside the buyer’s own suburb, compared with purchases of cannabis and amphetamines. Opinions on how risky it was to buy illicit drugs were sharply divided, with large proportions of respondents saying that it was either 'not at all risky' or 'very risky' to buy illicit drugs. A similar pattern was found when respondents were asked how risky it was selling illicit drugs.