PIP: AIDS and HIV present many challenges for the scientific community and people involved in the design of control and intervention programs. These challenges are usually addressed by researchers in the developed world who are interested only in the effect of their findings and programs in their own countries. HIV/AIDS, however, is now a disease of the developing world, with an estimated 95% of the world's 30 million people ever infected with HIV by 2000 located in the developing world. HIV infection and AIDS in the developing world is more than a medical problem, with far-reaching demographic, economic, and social impacts upon individuals and family structures. Controlling sexually transmitted diseases and HIV requires traditional medical and educational responses, but there are also basic sociological and economic factors which constrain the implementation of control programs and must be addressed. Any solution must address all elements which create and fuel this mainly sexually transmitted pandemic. The issue of rights and responsibilities is also becoming more important with the arrival of potential vaccines and therapeutic interventions which will need to be tested in populations with a high prevalence of HIV infection.