Providing patients with information is fundamental to respecting autonomy. However, there may be circumstances when information may be withheld to prevent serious harm to the patient, a concept referred to as therapeutic privilege. This paper provides an analysis of the ethical, legal and professional considerations which impact on a decision to withhold information that, in normal circumstances, would be given to the patient. It considers the status of the therapeutic privilege in English case law and concludes that, while reference is made to circumstances when information (primarily in relation to risk disclosure) may be withheld, further clarification is required on the status of therapeutic privilege. I suggest there has been shift in English law relating to the standard of information disclosure towards one set by the test of the reasonable, prudent patient. It is this shift that necessitates the existence of a therapeutic privilege which enables doctors to withhold information that would usually be given to the patient in order to prevent serious harm. I then explore the professional guidance in relation to information disclosure and how this relates to the legal position. There are strong ethical arguments in favour of disclosure of information to patients. In light of these, further clarification is required to identify and define the grounds on which this exception exists, the information that could lawfully be withheld and how this exception extends to rest of the health care team, particularly nurses. As such, explicit ethical and legal scrutiny of therapeutic privilege is needed in order to consider how this concept might be articulated, constrained and regulated.