Background: Exercise is encouraged to promote health, but it can be a trigger for sudden cardiac arrest (SCA) in individuals with underlying cardiovascular disease. In 2002, the American Heart Association and the American College of Sports Medicine issued recommendations for the presence of automated external defibrillators (AEDs) in health and fitness facilities. Objective: To assess emergency response planning for SCA and review the prevalence and past utilization of AEDs in health and fitness facilities in King County, WA. Methods: A cross-sectional survey was conducted in 2008 of health and fitness facilities (N = 136) in King County, WA, assessing the 2002 American Heart Association guidelines on AEDs and emergency response planning for SCA. Results: Sixty-three (46%) of 136 facilities completed the survey. Thirty-five percent of the total facilities had < 500 members, 21% had 500 to 1500 members, 16% had 1501 to 2500 members, and 29% had > 2500 members. Sixty-eight percent had an established emergency response plan for SCA. Only 40% of facilities had > 1 AED on site (mean, 1.7; range, 0-6). Fitness centers with > 1500 members (71%) were more likely to have an AED on site compared with those with < 1500 members (14%) (P < 0.0001). Of the staff trained in cardiopulmonary resuscitation, 83% were fitness instructors, 73% were administrators, and 58% were front desk personnel. Four facilities reported an incident of SCA within the 12 months prior to completing the survey, which was a 6.4% incidence of SCA in responding facilities. All SCA cases occurred in facilities with > 1500 members. Only 2 of the 4 facilities with an SCA had an on-site AED. The individuals who had SCA were all men aged 50 to 65 years, with 2 men successfully resuscitated at the facility. Conclusion: There is a substantial gap in guideline implementation between national recommendations and current emergency response planning for SCA in health and fitness facilities. Health and fitness facilities are strategic locations to place AEDs in an effort to improve outcomes from exercise-related SCA. Facilities with general memberships of > 1500 are encouraged to have on-site AEDs, given the high incidence of SCA. © The Physician and Sportsmedicine.