Colorectal cancer is the second leading cause of cancer-related deaths in the United States. During 1999, approximately 129,400 new cases of colorectal cancer will be diagnosed, and 56,600 persons will die from the disease. In 1996, the U.S. Preventive Services Task Force (USPSTF) recommended the use of specific screening tests (i.e., annual fecal-occult blood testing [FOBT] and/or periodic flexible sigmoidoscopy for persons aged > or =50 years) to reduce colorectal cancer-related mortality. In 1997, the American Cancer Society and an interdisciplinary task force developed guidelines that recommend one test or a combination of several tests for colorectal cancer screening. To estimate the proportion of the U.S. population that received colorectal cancer screening tests, CDC analyzed data from the 1997 Behavioral Risk Factor Surveillance System (BRFSS) on the use of a home-administered blood stool test, or FOBT, and sigmoidoscopy/proctoscopy. This report summarizes the results of this analysis, which documents low rates of use of colorectal cancer screening tests.