This article describes an exploration of the subjective experiences of self-injurious behaviour from the perspective of a woman with mild intellectual disabilities, Catherine (pseudonym). At the time of the study, Catherine was detained in a medium secure unit for adults with intellectual and associated disabilities, and had lived there for approximately 4 years. The study draws together her views and explores her understanding and experiences of her self-injurious behaviour using a qualitative, phenomenographic method. Catherine agreed to participate in in-depth discussions with the researcher, a nurse who had previously worked closely with her. The results offer sections of transcripts to illustrate the direction and focus of the discussions, which emphasize service issues and functions of Catherine's self-injury.