Doctors are exhorted to be candid with their patients when clinical errors occur. This paper discusses the history of candour in surgical law as well as recommendations resulting from the Mid Staffordshire public inquiry. It also looks at why candour is necessary and where the threshold should lie. Provided surgeons understand that a duty of candour is engaged at a certain threshold of harm, then disclosure of misadventure to patients or their relatives becomes simply a matter for clinical judgement, just in the same way as a surgeon judges which potential operative complications need to be disclosed during the consenting process.