The AIDS Clinical Trials Group network (ACTG) is one of the largest HIV clinical trials organizations in the world, playing a major role in setting standards of care for HIV infection and opportunistic diseases related to HIV and AIDS in the United States and the developing world. The ACTG is composed of, and directed by, leading clinical scientists in HIV/AIDS therapeutic research. The ACTG is funded by the Department of Health and Human Services, National Institutes of Health through the National Institute of Allergy and Infectious Diseases.