One of the most important gastroenterological emergencies is acute pancreatitis. It is classified into mild, moderately severe, and severe pancreatitis depending on occurring complications. Establishing etiology and assessing disease severity is the first step of the management. Severe pancreatitis is encountered in 25% of patients and carries the highest mortality. The therapy in these cases is structured on 4 interventions: fluid resuscitation, nutritional support, pain management, specific measures addressed to etiology or complications. Fluid resuscitation for prevention of necrotizing pancreatitis is the foundation of early management. Quality of life in these patients relies on prompt pain management. Early enteral nutrition might reduce mortality, multiple organ failure and infection rate when compared to late enteral nutrition and parenteral nutrition. Pseudocysts and infected necrosis can complicate severe pancreatitis. These symptomatic patients will need appropriate interventional maneuvers depending on imaging and disease extension. Antibiotics should only be given when infection is highly suspected, particularly when necrotizing pancreatitis is involved. Percutaneous drainage is recommended when the collected necrosis has less than 1 month from constitution. In walled-off pancreatic necrosis, endoscopic drainage and subsequent necrosectomy is preferred to percutaneous drainage. Surgery has to be taken into account after failure of endoscopical/percutaneous procedures, intra-abdominal compartment syndrome, or acute on-going bleeding.