The closed-door PhD and doctoral viva voce--the approach adopted in the United Kingdom--is esteemed by some as being a valuable academic tradition. However, an increasing body of literature and research has raised concerns about the quality, transparency, reliability and validity of this viva format. This systematic literature review aims to explore the closed-door viva from the candidate perspective. Eight studies, encompassing 267 participants, were included. Themes which emerged from a narrative synthesis of the data were: emotional response; psychological impact; power; examiner conduct (i.e. questioning techniques and interpersonal style); fairness; and practical and procedural issues. A great deal of variation was found across all accounts. Whilst some were indicative of positive and constructive viva experiences, there were also concerning reports of candidate distress as a result of examiner conduct, behaviour and use of positional power. Implicit and explicit reference was made to the lack of fairness. Given that concerns regarding the closed-door viva are now well-established, results are discussed with reference to recommendations for change; ultimately, to ensure best practice in PhD and doctoral assessment in the UK as well as to offer academic providers in other countries valuable insights into this form of viva.