Propofol infusions for the induction and maintenance of anaesthesia are associated with many advantages. In some units their cost is thought to be prohibitive and limits their use. We have analysed the drug costs within a Day Surgery Unit over a 4-year period in order to quantify the cost of the increased use of these infusions. In our unit this has not resulted in increased anaesthetic drug costs. We therefore advocate the continued use and development of these techniques which have been shown to have many advantages both to patients and to the smooth and efficient running of theatre units.