Objectives: To develop and pilot a questionnaire based assessment of the importance patients place on medical confidentiality, whether they support disclosure of confidential information to protect third parties, and whether they consider that this would impair full disclosure in medical consultations.Design: Questionnaire administered to 30 consecutive patients attending a GP surgery.Results: Overall patients valued confidentiality, felt that other patients might be deterred from seeking treatment if it were not guaranteed, but did not think that they would withhold information for this (...) reason themselves.Conclusions: When presented with brief details of five clinical situations in which a breach of confidentiality might be considered, a clear majority of subjects believed that doctors should disclose information in two of the situations, but subjects were not confident that doctors would do so. In three situations, about half felt that disclosure was justified—these included the only scenario in which disclosure was clearly mandated by statute. There was little change in patients’ general attitude to confidentiality after considering the scenarios. However, the views expressed were often inconsistent with responses to the clinical scenarios, suggesting that complex opinions were not accurately reflected in the responses. The format of the questionnaire has been amended, and the study will be repeated with other groups of patients. (shrink)