An audit at the Queensway Anxiety Management Clinic of 2014 children, referred for dental treatment, showed that relative analgesia by inhalation of nitrous oxide and oxygen failed in 40% of cases successfully to complete treatment. We therefore investigated the efficacy of a new inhalation conscious sedation technique, which reduced the need for general anaesthesia. Seventy-five children aged 3-15 years were given inhalation conscious sedation, with sevoflurane 0.1-0.3% and nitrous oxide 40% in oxygen. In 69 children (92%), the dental treatment was completed successfully. Most children (93%) had recovered fully within 10 min without side-effects. Treatment was fully accepted by 88% of children and 91% of their parents. The use of sevoflurane in low concentrations to supplement nitrous oxide and oxygen for conscious sedation in children appears to be safe and effective and further study is currently in progress.