Book excerpt: An estimated 5-6 lakh people die every year due to sudden cardiac death (SCD) i.e., an unexpected death that occurs within an hour of collapse. This amounts to 10% of total mortality and 1/5 th of all cardiovascular deaths. In sudden cardiac arrest, a sudden dangerous rhythm disturbance of the heart occurs, stopping blood flow to vital organs. Permanent brain damage occurs if the circulation is not restored within 3 to 4 minutes, and hopes of survival become remote by the time they are shifted to hospitals. On-the-spot bystander action in providing a life-saving cardiopulmonary resuscitation (cardiac massage) or CPR and early shock to the chest can improve survival by 60 to 80%. This manual comprehensively covers all aspects of sudden cardiac arrest across various age groups and situations. Containing 40 Chapters, 12 Annexures and 175 References, it delves deeply into the historical evolution and latest medical management protocols of this life threatening emergency. The manual will serve as a valuable reference book for all doctors, nurses and para medical staff posted in critical care units, casualty and the periphery.