A double-blind randomised study was designed to assess the value of oral midazolam in patients undergoing minor oral surgery. 30 young healthy Hong Kong Chinese with bilateral symmetrical impaction of lower third molars to be surgically removed in 2 visits, were included in the study. Randomly selected, a powdered midazolam tablet or placebo was given on the 1st visit and the alternative on the 2nd visit. 45 min were given for the drug to act. Surgical removal of the teeth was carried out by a single operator, randomly, one side being done at one visit. The majority who had midazolam were relaxed during the operation. Nearly 75% had partial to complete amnesia. Midazolam sedation lasted about 45 min, produced good operating conditions and stable vital signs with adequate verbal response. The main adverse effects were drowsiness and dizziness on the same day. The majority had never heard of oral sedation being available to supplement local anaesthesia. The majority preferred midazolam to placebo and preferred to have local anaesthesia supplemented with oral sedation for minor oral surgery in the future.