Harm reduction is part of a comprehensive approach to dealing with the harms of drug use. Although the evidence to support implementation of harm reduction strategies for illicit drug use is abundant, it is unlikely that scientific knowledge alone will be enough to facilitate the adoption of harm reduction strategies in many health-care settings. The authors examine the ethical, legal and social context of harm reduction as it pertains to illicit drug use to assist nurses in providing safe, competent and ethical care. Included is an examination of values and accompanying responsibility statements from the Canadian Nurses Association's Code of Ethics for Registered Nurses that can guide nurses in their ethical reflection and provide insights into ethical practice.