This paper evaluates the communication of information to physicians who provide off-hours coverage to inpatients in two Family Practice residency programs. METHOD: To describe the importance and accessibility of clinical information used by on-call residents in covering hospital patients, we administered a questionnaire. Then following the use of a new computerized sign-out system in one of the programs, residents filled out the same questionnaire again. RESULTS: Residents felt that a "to do" list and information about the patient's "code status" were the most important data desired from sign-out sheets. However, 69% of residents in both programs felt that provision of this information was normally poor. Nearly all of the residents in Buffalo, using an entirely handwritten sign-out sheet, felt it was in need of improvement. Residents in Pittsburgh, using a summary aided by the hospital's computer print-out, felt this need much less acutely. After implementation of a new computerized sign-out sheet in Buffalo, residents indicated a slightly higher level of satisfaction. The work of data entry and re-entry into the computer was unpopular and inefficient. CONCLUSION: The present method of transferring information at the end of a work day is not satisfactory for residents. Provision of data summaries from existing hospital information systems is a good first step in improving data transfer. A further study of more comprehensive automated sign-out systems is important, because of the increasing discontinuity of house officer care.