Deliberate self-harm (DSH) is a perplexing and distressing phenomenon that has received considerable publicity in recent years. It takes many forms, some of which are culturally acceptable while others are considered to be anti-social and/or mental health problems. It affects a significant proportion of the population, with previous studies in the United Kingdom and elsewhere finding between 5% and 15% of young people with a history of self-harm. However, there is little published research on DSH in educational settings and how it is handled in schools and universities. This paper reports a mixed-method study of DSH amongst students in a university in the Greater London area. The methodology took the form of a questionnaire survey (n = 348) of mainly undergraduate students, semi-structured interviews (n = 30) with students and staff, and two focus groups (n = 9). Significant levels of self-harming behaviours were found, including cutting, binge-drinking, risk-taking, eating disorders and substance abuse. Form and prevalence were found to vary by gender, ethnicity and programme of study, although neither the statistical nor the policy significance of these variations appeared to be great. Interviews accessed case descriptions and perceptions of prevalence, awareness and institutional response, and raised questions about the impact of DSH on other students and on the staff who provide support. Professional and ethical issues raised by cases of DSH were a major topic for discussion at interview. The preliminary findings were presented to two focus groups that considered their implications for policy and practice, including counselling, student induction, and training and supervision for staff. The paper concludes with a typology of self-harming behaviours in terms of their severity, visibility and cultural acceptability. It is hoped that this may be of use to universities and other institutions in developing policies and procedures for dealing with this issue. (Contains 10 tables, 2 figures and 7 notes.)