Clear communication between primary and secondary care is essential to prevent prescribing errors, especially in the case of psychiatry where medication is frequently altered and prescribing may be the responsibility of either the GP or the specialist. Here, Dr Robinson describes an audit carried out at the local elderly day treatment service to examine the discrepancies between GPs' records of medication and those of the day service, and to investigate how improvements could be made. Copyright © 2008 Wiley Interface Ltd