All out-of-hospital cardiac arrest advanced life support (ALS) trip sheets were collected from January 1980 through December 1985 for this suburban-rural system. Information was extracted according to a uniform reporting format. In our study, 18% of patients with early CPR (less than four minutes) and early ALS (less than ten minutes) survived to hospital discharge, compared with 7% with early CPR and late ALS, 6% with late CPR and early ALS, and 3% with both occurring late. Although 75% of the survivors had ventricular tachyarrhythmias as initial rhythms, bradyasystolic arrests were not uniformly lethal, even with long CPR and ALS times. This study supports the need for early CPR in the prehospital care of potential sudden-death victims. We recommend, with qualification, this reporting format to emergency medical services systems to describe their cardiac arrest experience.