The International HIV/AIDS Alliance, the World Health Organization (WHO) and the UNAIDS Secretariat welcome readers to this handbook.

Designed to be a useful resource for the different groups involved in treatment for HIV-related conditions, the handbook is also an implicit tribute to these groups. It is a concrete acknowledgement that, without their work, the global response to AIDS would be much smaller - and much less effective - than it is today.

Groups of people living with HIV/AIDS (PLWHA), nongovernmental organizations (NGOs) and community-based organizations (CBOs) have been at the forefront of prevention and care since the world first became aware of the epidemic two decades ago. Instead of passively leaving these tasks to the medical profession or public health authorities, they have become partners in providing HIV-related commodities and services - and, in some places, they have been the only providers. They have also courageously built roles for themselves as advocates and teachers, changing the way the world thinks about HIV/AIDS and responds to the people who live with it. In doing so, they have built hope, spread important skills and ensured better delivery of HIV/AIDS-related services and commodities.

Recognizing that these groups remain a key resource in the global response, this handbook aims to widen their participation even further by providing them with a useful collection of information and tools. However, the word 'providing' implies one-way giving when, in fact, the creation of this handbook has been a two-way process: while the Alliance, WHO and UNAIDS Secretariat may be providing the finished product, the essential 'raw material' was provided by dozens of individuals and groups in Africa and Asia. Their generous and enthusiastic participation during the design and field-testing stages gave the handbook the benefit of their experience and expertise, and kept it focused on the practical needs and challenges of providing treatment to people living with HIV/AIDS.

This process echoes the creation of another book a decade ago - the AIDS Home Care Handbook - which was published by WHO after extensive consultation with NGOs working in HIV/AIDS care in developing countries. That pioneering book has been used all over the world, freely adapted to fit widely different conditions in a variety of places.

This new handbook proceeds in the same spirit of partnership. The Alliance has contributed its strong field experience and expertise in collaboration with local NGOs and CBOs. WHO has overseen the technical content, in particular on drug management issues. The UNAIDS Secretariat, as a global advocate for mobilizing NGOs' and CBOs' entry into the field of care, initiated the handbook's development, brought in the Alliance and many other NGOs and CBOs, and provided funding.

It is hoped that this new handbook will prove as useful as the earlier book, which it does not replace but complements. We hope that it will encourage groups already involved in HIV/AIDS care to extend the services they provide, and that it will encourage other groups (perhaps doing some other HIV-related activity, such as prevention and support, or in other fields of health, such as family planning and reproductive health) to get involved.

If the global response to HIV/AIDS can be thought of as a chain, then treatment is one of its essential links. We hope that this handbook will help groups around the world to find their own ways of reinforcing that link - and, in doing so, strengthen the entire chain.