Strategies for preventing infection with human immunodeficiency virus (HIV) emphasize testing to identify infected persons and ensure access to appropriate medical care, treatment, and prevention services. To determine the number of persons who were tested for HIV during the preceding 12 months, CDC analyzed data from both the 2002 National Health Interview Survey (NHIS) and the 2002 Behavioral Risk Factor Surveillance System (BRFSS) survey. This report summarizes the results of these analyses, which indicated that, in 2002, approximately 10%-12% of persons aged 18-64 years in the United States reported being tested for HIV during the preceding 12 months, an estimated 16-22 million persons. Continued measurement of HIV testing by health surveys such as BRFSS and NHIS can be used in combination with program data and other surveys of populations at high risk to determine the impact of HIV strategies on increasing testing.