A self-report scale (Self-Injury Motivation Scale; SIMS) to assess motivation for self-injury was developed. Relationships among motivations for self-injurious behaviour, characteristics of self-injurious behaviour, & psychopathology were explored among 99 consecutively admitted inpatients. The scale was found to have good reliability & validity. A high score suggested distinct psychopathology. Several factors on the scale differentiated motivations for self-injurious behaviour. Patients with different SIMS factor profiles had different psychopathology. (43 refs.)