A handoff is the transfer of a patient's care from one provider to another. It usually involves both a verbal and written exchange of information. Although written handoff sheets are critical to good patient care, there is little data on the quality of information they contain. We conducted a study to assess the accuracy of handoff sheets used in one Minneapolis internal medicine residency program. We compared the accuracy of information about code status, medication allergies, medications, and problems recorded on the handoff sheet with that in the patient's medical record. We found errors were common in resident handoff sheets. Only 83 (19%) of 428 handoff sheets contained no errors. The most common error was one of omission on the medication list (69% of the handoff sheets contained a medication omission). The percentage of patient handoff sheets with code-status errors was 5.7%, and the percentage with medication allergy errors was 2.8%. Important problems were omitted from the problem list in 22% of cases.