Previous studies have reported that a letter from the patient's General Practitioner (GP) and a short GP consultation led to reduced intake among long-term benzodiazepine (BZD) users, with no evidence of a deterioration in general or mental health. We aimed to replicate these earlier findings in a single, prospective RCT and compare the effectiveness of the two brief interventions. 273 long-term BZD users (≥6 mos) identified from repeat prescription computer records of 7 general practices were randomised to: (i) usual GP care + assessment only; (ii) the offer of a short consultation with the patient's GP (or practice nurse/ practice pharmacist); (iii) a letter signed by the GP advising gradual reduction in BZD intake. The typical patient entering the study was an elderly woman taking BZDs primarily for sleeping problems. Results showed significantly larger reductions in BZD consumption in the letter (24% overall) and consultation (22%) groups than the control group (16%) but no significant difference between the two interventions. There was no evidence that brief interventions increased psychological distress or had an adverse effect on general health. We conclude that, among long-term BZD users considered by GPs to be suitable to receive advice encouraging them to cut down BZD intake, brief intervention, either in the form of the offer of a short consultation or a letter from the patient's GP, is effective in leading to reduced BZD intake without adverse consequences.