Treatment duration was associated with better outcomes and the longer drug users were in treatment (up to 10 months in some cases), the fewer followup offenses were committed. The results suggest an association between treatment and falls in crime. Since the results do not prove that these falls in crime were solely the results of prescribing, further research is justified. There is already evidence to indicate that drug users in treatment commit fewer crimes, although this is mostly based on users’ self-reported criminal activity. In this study, anonymous data from the Police National Computer was matched to information in the National Treatment Agency for Substance Misuse’s (NTA’s) National Drug Treatment Monitoring System database. Researchers examined a sample of opiate and crack users who had recently offended but had not been jailed, and had started drug treatment in the community. The number of offenses committed dropped by almost half following the start of treatment, from 4,381 to 2,348. The biggest category, greedy crime, fell from 1,234 to 635. Reductions were consistent across the board for a range of crimes, although a higher proportion of the later round of offenses were for breaches of previous sentences rather than new crimes. In a subsample of offenders who had committed crimes that qualified for testing on arrest, the number of followup offenses committed fell by 61 percent; from 2,023 to 793. The results suggest that those who did commit further offenses were more likely to have been serial offenders. Figures, tables, and references