PROBLEM: Continuous monitoring of behaviors that increase the risk for chronic diseases and use of preventive practices are essential for the development, implementation, and evaluation of health promotion programs and policies, and other intervention strategies to prevent morbidity and mortality. Data from states/territories, selected metropolitan and micropolitan statistical areas (MMSAs), and counties provide the impetus for policymakers and other stakeholders to develop and promote the improvement of their community's overall health status. REPORTING PERIOD COVERED: Data in this report were collected during January 1-December 31, 2004, from states/territories, MMSAs, and counties that participated in the 2004 Behavioral Risk Factor Surveillance System (BRFSS). DESCRIPTION OF THE SYSTEM: BRFSS is an ongoing, state-based, random-digit--dialed telephone survey that employs a multistage cluster design. BRFSS collects information on health risk behaviors and preventive health practices related to the leading causes of death from the U.S. civilian, noninstitutionalized population aged > or =18 years. During 2004, a total of 49 states, the District of Columbia (DC), Puerto Rico, and the U.S. Virgin Islands participated in BRFSS. Among these states and territories, completed surveys were collected from a selection of 134 MMSAs and 199 counties. RESULTS: Prevalence of high-risk behaviors for chronic diseases, awareness of specific medical conditions, screening for certain cancers, and use of preventive health services varied substantially by state/territory, MMSA, and county. The proportion of the population that achieved Healthy People 2010 (HP 2010) objectives also varied by state/territory, MMSA, and county. In 2004, HP 2010 objectives for 100% health-care coverage and vaccination for pneumonia and influenza among persons aged > or =65 years were not achieved by any state/territory, MMSA, or county. Twelve states/territories, 47 MMSAs, and 74 counties achieved the HP 2010 objective of < or =20% of adults engaged in no leisure-time physical activity or exercise. The HP 2010 objective to reduce the proportion of adults who currently smoke cigarettes to < or =12% was achieved by two states/territories, four MMSAs, and six counties. One MMSA and one county achieved the HP 2010 target of < or =6% who engage in binge drinking during the month preceding the survey. The HP 2010 target of < or =15% of adults who are obese was obtained by one MMSA and eight counties. The HP 2010 objective to reduce the proportion to <20% for older adults who have had all of their natural teeth extracted was achieved by 23 states/territories, 51 MMSAs, and 45 counties. The HP 2010 target for adults aged > or =50 years who have ever received a sigmoidoscopy is 50%. BRFSS measured both sigmoidoscopy and colonoscopy. Using this measure, 38 states, 110 MMSAs, and 154 counties achieved the 50% goal. Four counties achieved the HP 2010 objective of 50% for adults who received a blood stool test within the previous 2 years. The HP 2010 objective to increase the proportion of women aged > or =18 years who had a Papanicolaou (Pap) test within the preceding 3 years is 90%. Twenty-four MMSAs and 49 counties achieved this objective. The HP 2010 objective for women aged > or =40 years who have received a mammogram within the preceding 2 years is 70%. Thirty-nine states, 112 MMSAs, and 168 counties achieved the objective. This report includes several risk behaviors and conditions that, although not included in HP 2010 goals, are important public health problems. These include self-reported fair-to-poor health status, heavy alcohol consumption, asthma, diabetes, and prostate cancer screening. The 2004 BRFSS data indicate great variability in the prevalence of self-reported fair-to-poor health status (5.7%-34.8%) and use of prostate cancer screening (34.7%-65.2%) by states/territories, MMSAs, and counties. Among these areas, the prevalence of current asthma ranged from 4.1% to 12.4%, and the prevalence of diabetes ranged from 3.2% to 12.5%. INTERPRETATION: The findings in this report indicate variations in health risk behaviors and use of preventive health screenings and health services among adults at the state, local, and county levels. These variations substantiate the continued need for public health surveillance in designing, implementing, monitoring, and evaluating public health policies and health-care use programs to reduce morbidity and mortality from the effect of high-risk health behaviors and subsequent chronic disease outcomes. PUBLIC HEALTH ACTION: Data from BRFSS are essential for monitoring prevalence of high-risk health behaviors, specific diseases, and use of preventive health services; dictating the design, focus, implementation, and evaluation of prevention health programs and strategies; and monitoring progress toward obtaining local, state, and national health objectives. Data from the 2004 BRFSS indicate a continual necessity to initiate and implement health promotion strategies for identifying specific health risk behaviors and practices and for assessing progress toward achieving disease prevention and health promotion objectives at state and local levels throughout the United States.