Despite the many justifications for protecting patient confidentiality, we recognize that confidentiality cannot be absolute. Our world of automated information and easy access and storage poses many threats to confidentiality. This paper has described a survey conducted at the NIH Clinical Center to assess the knowledge, attitudes, and behaviors of clinical physicians and nurses about confidentiality of patient information. The survey findings demonstrate the need for reminders and increased awareness about confidentiality in our setting. Most of the survey respondents had a good knowledge of what was expected of them, and they believed that confidentiality was important and maintaining it was their responsibility. Of interest was that in several simulated clinical situations, there was a discrepancy between what respondents indicated they should do and what they thought they would do. The biggest discrepancies appeared in situations that involved overhearing a patient conversation on the elevator, approaching an unfamiliar person who is reading a medical record in the nurses' station, and answering a patient's inquiry about the status of another patient. The findings support the speculation that this difference may be attributed to discomfort or decreased awareness, and not necessarily to lack of knowledge. Results indicate that policies and administrative expectations should be frequently communicated and enforced, and that educational programs that address issues of confidentiality should be provided. The results of this survey have been influential in guiding educational strategies and administrative activities at the clinical center. The clinical center initiated a confidentiality awareness campaign, displaying a new poster every three months in strategic locations and distributing other tangible reminders (such as pens, magnets, and buttons) containing the same confidentiality message.(ABSTRACT TRUNCATED AT 250 WORDS)