Out-of-hospital cardiac arrest still has a survival rate of less than 10%. Starting data collection through multicenter registries is essential in order to identify the most appropriate interventions to improve survival rates. The LIFE registry is a prospective, observational, and multicenter study, non-profit. The primary objective of the study is to assess the survival of out-of-hospital cardiac arrests in the entire Emilia-Romagna region, both in the acute phase and in the medium- to long-term follow-up. Participating centers include: Azienda USL Romagna, Azienda USL di Bologna, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Azienda USL di Imola, Azienda USL di Ferrara, Azienda Ospedaliero-Universitaria di Ferrara, Azienda USL di Modena, Azienda Ospedaliero-Universitaria di Modena, Azienda USL-IRCCS di Reggio Emilia, Azienda USL di Parma, Azienda Ospedaliero-Universitaria di Parma. For each patient, data will be collected on the cardiac arrest event, baseline clinical data, and follow-up information reported in the data collection form (CRF). Data sources include: Territorial emergency systems (AAT 118), Emergency Departments and hospital departments of the participating centers, patient clinical documentation, data from clinical follow-up and/or telephone follow-up. Secondary objectives of the study include: evaluating survival in relation to the type of first aid (bystander, 118, emergency responders), the use of AEDs available in the area, any apps (AED RESPONDER), the application of resuscitation maneuvers, survival before hospitalization for all causes, survival of patients admitted alive to the Emergency Department, at 30 days after the arrest, at 1, 3, and 5 years after the arrest, neurological outcome at discharge and at 30 days from the arrest, and optionally in the medium- and long-term follow-up. Regarding the evaluation of times, intervention times will be considered to potentially develop a reduction plan (time from 118 call to arrival at the scene, time from arrival at the scene to arrival at the Emergency Department, time from first responder intervention to application of the AED).