To date, very little research has focused specifically on exploring clinicians’ understanding and treatment of self-injury. My study was an attempt to address this gap in the literature and to fill in perspectives and voices not previously articulated. In this study I explored clinicians’ understanding of self-injury, their discourses about their treatment models and their perceptions of their clinical effectiveness and failures in their work with self-injuring clients. I also examined the sources of knowledge that contributed to clinicians’ understanding of self-injury and of those who engage in this behaviour. Eight participants were selected using snowball and criterion sampling methods. These participants were all mental health clinicians from a variety of professional disciplines and who practiced a range of different treatment modalities with self-injuring patients. Qualitative in-depth interviewing was the primary method of generating data and discourse analysis was the mode of analysing the data in this research study. The findings of my study suggested that the majority of the clinicians did not have a distinct model for considering self-injury and treatment approaches for working with self-injuring clients. Rather, they created discourse communities of “an other” to formulate their beliefs about self-injury and its treatment. They also relied predominantly on their clinical practice with self-injuring patients for comprehending and treating self-injury. In relation to their current treatment practice effectiveness and failures the clinicians seemed to draw on two distinct discourses, an “expert discourse” and an “inquiry discourse” and appeared to have little or no systematic way of thinking or conceptualising “progress” with regard to self-injury. Implications for the education and training o f clinicians about the phenomenon and treatment of self-injury are discussed, with particular reference to the application o f an inquirer’s discursive approach. In addition, recommendations are made for future research and directions in this field, in terms of replicating this study in other countries beyond Ireland and also including the narratives of self-injuring patients’ discourses about their experience of various treatment modalities.