Introduction

This chapter introduces the notion of nonsuicidal self-injury (NSSI). NSSI encompasses a wide variety of behaviors including but not limited to carving or cutting of the skin and subdermal tissue, scratching, and burning. NSSI became an indelible part of the mental health landscape in populations of all types. Moreover, NSSI occurs across cultures, geography, and population which eventually became a leading signal for suicide risk. The chapter looks into Bronfenbrenner's ecological systems theory and a transdiagnostic perspective at the levels of conceptualization, therapeutic assessment, intervention, and treatment as per the Research Domain Criteria. It considers case vignettes and summaries of implications for research, clinical practice, and intervention.