In recent years, a consensus has developed among international NGOs and UN agencies working to support children affected by HIV and AIDS, with general agreement around key principles and priorities. There is also increasing recognition that investment in children's early years of life gives the greatest returns. Yet far too little has been done to put principles into practice and there is an urgent need for concerted government action. Although there has recently been more focus on how HIV and AIDS affect young people, the issue of children affected by AIDS is still relatively neglected, and where very young children are concerned, their invisibility is striking. This report, the first in a series, highlights some of the policy challenges facing the people and organisations responsible for putting plans and strategies to address the impact of HIV and AIDS on children in their early years into practice.