The application of syndrome analysis in clinical practice has tended to rely on rather qualitative diagnoses by the neuropsychologist. The present paper proposes the use of a decision theory method which enables a systematic approach to be made to neuropsychological diagnosis. It is argued that the proposed method not only aids diagnostic decision making but also enables probabilities to be associated with particular prognostic statements. In this way the method is useful for guiding testing procedures and optimizing treatment programmes for particular patients.