The Energy Institute, on behalf of Shell, commissioned a rapid review of psychological safety. Psychological safety can be described as the willingness of people to express an opinion, admit mistakes or unsafe behaviours, without fear of being embarrassed, rejected or punished. Psychological safety plays a role in facilitating the reporting of errors and unsafe behaviours – thereby enabling these to be identified, learnt from and improvements made to prevent repetition of errors and unsafe behaviours. Psychological safety is particularly important in hierarchical organisations, often with complex systems, where error may have serious safety consequence, and where individuals or organisations are held responsible for adverse consequence. Interventions to enhance psychological safety include tools to support analysis of causes of error and behaviours, displayable effort by management and the organisation to build trust and teamwork between staff and themselves as well as supporting and encouraging safety related behaviour.