This Nutrition Policy Paper is based on the ACC/SCN Symposium on Nutrition and HIV/AIDS held in Nairobi in April 2001. The objective of the symposium was, firstly, to stimulate collaboration between the nutrition and HIV/AIDS communities. The second objective was to examine a broad range of nutrition issues that have a direct bearing on policies and programmes aimed at stemming the spread of HIV and mitigating the worst effects of AIDS. This report provides technical information, policy guidance and informal reflections. It also contains the ACC/SCN statement arising from the symposium, and in Annex 1, a fact sheet on the interactions between nutrition and HIV/AIDS.