It is not known how many of the telephone calls received by family medicine residents get documented in a retrievable form. This descriptive study attempted to answer this question by comparing a university telephone operator's logbook to the files of after-hours encounter slips kept in a university based family medicine training program. Over a period of 10 weeks, 38% of the calls recorded by the operator were documented by residents in a retrievable fashion. Second-year residents documented calls significantly more than third-year residents, and all residents kept better documentation on calls that concerned young children. Documentation varied significantly among individual residents but was not affected by the day or time of calls. These results suggest that having a system for recording after-hours telephone calls is not sufficient to ensure adequate documentation. Monitoring after-hours call records may provide a solution.