Cardiopulmonary resuscitation (CPR) in special circumstances includes the emergency intervention for special causes, special environments and special patients. Special causes cover the potential reversible causes of cardiac arrest that must be identiied or excluded during any resuscitation, divided into two groups, 4Hs and 4Ts: hypoxia, hypo-/hyperkalaemia and other electrolyte disorders, hypo-/hyperthermia, hypervolemia, tension pneumothorax, tamponade (cardiac), thrombosis (coronary or pulmonary) and toxins. The special environments section includes recommendations for the treatment of cardiac arrest occurring in speciic locations: cardiac surgery, catheterisation laboratory, dialysis unit, dental surgery, commercial airplanes or air ambulances, ield of play, diicult environment (e.g. drowning, high altitude, avalanche and electrical injuries) or mass casualty incident. CPR for special patients gives guidance for the patients with severe comorbidities (asthma, heart failure with ventricular assist devices, neurological disease and obesity) and pregnancy women or elderly people.