Objective. To investigate errors in administering drugs by anaesthetists working in public hospitals in the Free State province. Methods. Anonymous questionnaires were distributed to doctors performing anaesthesia in public hospitals in the Free State, i.e. 188 doctors at 22 public sector hospitals. Outcomes included demographic information on respondents, information regarding the administration of anaesthetics, reporting of errors, and the occurrence of errors during anaesthesia. Results. The response rate was 46.3%; 48.8% were medical officers, and 39.3% of participants were involved in at least one event of erroneous drug administration. Registrars and specialists reported the most errors. Most events were of no clinical significance, caused no permanent harm to patients, and most commonly involved fentanyl and suxamethonium. Of the respondents, 23.8% indicated that they were aware of a South African standard for colour-coding syringe labels, and 92.9% indicated that they would report anaesthetic errors if a single reporting agency for such events existed. Conclusions. More than a third of participating anaesthetists were involved in a drug error at some stage in their practice. Preventive systems and precautionary measures should be put in place to reduce drug administration errors