To evaluate the effectiveness of different brief intervention strategies at reducing hazardous or harmful drinking in the probation setting. Offender managers were randomized to three interventions, each of which built on the previous one: feedback on screening outcome and a client information leaflet control group, 5 min of structured brief advice and 20 min of brief lifestyle counselling. A pragmatic multicentre factorial cluster randomized controlled trial. The primary outcome was self-reported hazardous or harmful drinking status measured by Alcohol Use Disorders Identification Test (AUDIT) at 6 months (negative status was a score of