AIDS: Health care providers who serve farmworkers are challenged by the geographical distribution of their clients, language differences, and opposition from Congress. At the 1996 National Farmworker Health Conference, clinicians and researchers considered how to deal with these challenges. The number of U.S. migrant and seasonal farmworkers, including their dependents, is estimated at 4.2 million. Ethnic and racial minorities, mostly Latinos and blacks, make up 85 percent of this population. Farmworkers' health is generally poor, and 44 percent have tested positive for tuberculosis. Farmworkers often live in poverty, a key barrier to health care. Living conditions are often unsanitary and overcrowded, further exacerbating medical problems. Between 1987 and 1992, the rate of HIV seroprevalence in the farmworker population increased 10 fold, from 0.5 percent to 5 percent. Dr. Stephen Raffanti, of Vanderbilt Medical Center, treats HIV-positive patients in Tennessee. Most HIV-positive farmworkers lack access to doctors experienced in AIDS care. Legislation being considered by Congress would limit the health care access of both legal and undocumented immigrants and hinder efforts to control infectious diseases.