In the United States, Hispanics are affected disproportionately by human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS). Although Hispanics accounted for 14.4% of the U.S. population in 2005, they accounted for 18.9% of persons who received an AIDS diagnosis. The rate of HIV diagnosis among Hispanics also remains disproportionately high; in 2005, the annual rate of HIV diagnosis for Hispanics was three times that for non-Hispanic whites. To better characterize HIV infection and AIDS among Hispanics in the United States, CDC analyzed selected characteristics of Hispanics in whom HIV infection was diagnosed during 2001-2005 and those living with AIDS in 2005. The results indicated that the mode of HIV infection for Hispanics varied by place of birth, suggesting that all HIV-prevention measures might not be equally effective among Hispanics and that HIV educational activities should address cultural and behavioral differences among Hispanic subgroups.