OBJECTIVE This prospective study was designed to establish the nature, frequency and sequelae of complications arising in patients receiving dental treatment under intravenous midazolam sedation. METHODS All patients attending the Sedation Department at New-castle Dental Hospital for intravenous sedation over a six-month period were audited. A standardised data-collection pro forma was designed in order to collect data relating to the patient, the sedation episode, the dental treatment and any complications arising. The published standard used in this study states that the incidence of complications should be no more than 8%. RESULTS Four hundred and one patients were included. The mean dose of midazolam administered was 7.6 mg with a mean titration rate of 0.9 mg/min. Complications were reported in 12 patients (3%), 11 of which were minor and one moderate. All complications were managed successfully within the department with no lasting sequelae. Treatment was completed in 382 (95.7%) patients, with failure to complete treatment in 17 (4.3%) patients due to disinhibition (1), poor cooperation (10), and the sedation wearing off (6). CONCLUSIONS The standard was met because complications arising were infrequent (3%) and predominantly minor in nature. Complications were managed conservatively and effectively, with all patients being discharged home the same day with no lasting sequelae. The study demonstrates that intravenous midazolam provides a safe sedation technique, suitable for adult dental patients in primary care, when administered by trained personnel on carefully selected patients and in accordance with nationally agreed protocols and guidelines.