In general, most, but not necessarily all, patients want truthfulness about their health. Available evidence indicates that truth-telling practices and preferences are, to an extent, a cultural artefact. It is the case that practices among nurses and doctors have moved towards more honest and truthful disclosure to their patients. It is interesting that arguments both for and against truth-telling are established in terms of autonomy and physical and psychological harm. In the literature reviewed here, there is also the view that truth-telling is essential because it is an intrinsic good, while it is argued against on the grounds of the uncertainty principle. Based on this review, it is recommended that practitioners ought to ask patients and patients' families what informational requirements are preferred, and research should continue into truth-telling in clinical practice, particularly to discover its very nature as a cultural artefact, and the other conditions and contexts in which truth-telling may not be preferred.