The relationship between psychiatric disorder (as measured by severity of psychoneurotic status and depression) and decision-making behaviour was examined in a sample of 39 hospitalised patients. Measures based on the conflict theory of decision-making of Janis and Mann (1977) and the expectancy-value theory of decision-making of Edwards (1961) were administered. Patients who scored highest on measures of psychoneurotic disorder--the Middlesex Hospital Questionnaire and the Beck Depression Inventory--were least confident about their decision-making. They also reported a high use of maladaptive decision-making coping patterns, in particular decision avoidance. Slightly over one-half of the patients demonstrated an ability to make rational decisions, while the remainder made either irrational decisions or avoided making any decision at all. Observation in the test session revealed that patients were strikingly slow in answering the questionnaires and often attempted to make no response. The importance of this area of research for patient assessment and treatment is discussed.