To evaluate the confidentiality of the patients' data in the electronic patient records designed by members of the Center for Clinical Computing in Boston, we examined the accessibility of the computer-stored medical records of two groups of patients at Boston's Beth Israel Hospital: celebrities, hospital employees, and their relatives (VIPs) and other patients (non-VIPs). We studied how often authorized clinicians gained access to computer-stored data on the two types of patients and whether look-up patterns differed if the data concerned a VIP. Our results suggest that the measures used to maintain data confidentiality at Beth Israel Hospital are adequate.