This paper describes the outcome of a nine-year post-anaesthetic followup program in a large teaching hospital (N = 112,721 anaesthetics). Between time periods 1975-78 and 1979-83, more seriously ill patients (higher ASA physical status) were being treated. Anaesthetic practice also changed, with an increased use of balanced (multiple drug) anaesthetic procedures, a decrease in the use of halothane and an increase in the use of monitoring. Nonfatal anaesthetic complications--intraoperative, recovery room and postoperative--were rare but there was an increase in the reported complication rate over time. From 1975-78, 7.6 per cent of all cases had at least one intraoperative complication and from 1979-83, this rose to 10.6 per cent of all cases. For recovery room complications, there was an increase to 5.9 per cent in 1979-83 from 3.1 per cent in 1975-78. In time period 2 there was a 9.4 per cent chance of having a postoperative anaesthetic-related complication, and a 0.45 per cent chance of a significant morbidity as a result. This represents an increase over time period 1 (8.9 and 0.40 per cent respectively). It is concluded that the anaesthetic experience, while associated with low mortality rates in recent years, is still associated with significant morbidity. It is conjectural at present whether this is reflective of preoperative patient status, anaesthetic practice, or other undefined variables associated with an operative experience.