OBJECTIVES: To estimate current rates of use of fecal occult blood testing (FOBT) and sigmoidoscopy or colonoscopy; to determine whether test use varies by demographic factors; and to compare 1999 rates of use with 1997 rates. STUDY DESIGN: The Behavioral Risk Factor Surveillance System is an ongoing, state-based random-digit-dialed telephone survey of the US population that collects various health behavior information, including the use of colorectal cancer (CRC) screening tests. POPULATION: In 1999, 63,555 persons 50 years of age or older responded to questions regarding FOBT and sigmoidoscopy or colonoscopy. OUTCOMES MEASURED: The proportion of survey respondents reporting having had FOBT and sigmoidoscopy/colonoscopy at any time; and the proportion reporting having had FOBT and sigmoidoscopy/colonoscopy within recommended time intervals. Data were recorded for the years 1997 and 1999, and analyzed according to various demographic factors. RESULTS: In 1999, 40.3% of respondents reported having had an FOBT at some time, and 43.8% reported having had a sigmoidoscopy or colonoscopy. Regarding recent test use, 20.6% of respondents reported having had an FOBT within the year, and 33.6% reported having had a sigmoidoscopy or colonoscopy within the past 5 years. Some demographic variation was noted. In 1997, 19.6% reported having had an FOBT within the year, and 30.3% reported having had a sigmoidoscopy or proctoscopy within the past 5 years. CONCLUSIONS: Use of CRC screening tests increased only slightly from 1997 to 1999. Usage remains low, despite consensus that screening for CRC reduces mortality from the disease. Efforts to promote awareness of, and screening for, CRC must intensify.