PART 1 Bruxism is regarded as a relatively esoteric area for psychologists, and this thesis therefore attempts to set out in a fairly comprehensive manner a review of the bruxism literature with special emphasis on the contribution made by psychology to the understanding of the aetiology and treatment of bruxism. This review consists of three chapters: Chapter 1 defines and justifies interest in bruxism, Chapter 2 discusses the dental and psychological treatment of this disorder and Chapter 3 discusses the importance of psychol- ogical factors in the aetiology of bruxism. PART 2 Arising from the discussion in Part 1, Part 2 is an investigation of the psychological assessment of bruxists. It involved the simultaneous assessment of both psychological factors and the level of nocturnal bruxism. Data was collected on both psychological and objective measures from a21 year old female over a six week period. The results indicated significant correlations between certain psychological indices and objective measures of bruxing behaviour. However, due to the number of correlations calculated, little credence can be given to these unpredicted significant effects. The question of psychological assessment of bruxists for the purpose of differential diagnosis was prior to this study virtually ignored. This study, while having obvious limitations, points to an interesting direction for further research.