BRFSS is a state-based, random-digit–dialed telephone survey of the noninstitutionalized, U.S. civilian population aged ≥18 years. Data collected by BRFSS include age, sex, race/ethnicity, marital status, educational level, employment status, household income, health-insurance coverage, assigned metropolitan statistical area (MSA) (i.e., containing a core urban area with a population ≥50,000), and state of residence. In 2005, a total of 129,416 persons in 21 states and DC responded to questions regarding history of heart attack and receipt of cardiac rehabilitation. Participants were asked, “Has a doctor, nurse, or other health professional ever told you that you had a heart attack, also called a myocardial infarction?” If the answer was “yes,” the participants were asked, “After you left the hospital following your heart attack, did you go to any kind of outpatient rehabilitation?” Participants who refused to answer the question or who responded “don't know/not sure” were coded as missing. The median response rate (i.e., the percentage of persons who completed interviews among all BRFSSeligible persons, including those who were not successfully contacted) among the 21 states and DC, based on Council of American Survey and Research Organizations (CASRO) guidelines, was 51.6% (range: 34.6%-66.7%). The median cooperation rate (i.e., the percentage of persons who completed interviews among all BRFSS-eligible persons who were contacted) was 74.3% (range: 63.2%-85.3%). The median response rate among all states in the 2005 BRFSS was 51.1% (range: 34.6%-67.4%).