Essentially, acute pericardial syndromes include acute pericarditis and cardiac tamponade. This article focuses on the diagnosis and management of acute pericarditis. In Spain, most cases of acute pericarditis whose etiology is not apparent at initial clinical presentation are either idiopathic or viral pericarditis, which follow a benign or self-limiting clinical course (although tamponade may develop in some patients). Knowledge of this basic epidemiologic fact is essential for the development of a rational management protocol that, on the one hand, avoids the unnecessary use of invasive pericardial diagnostic procedures in patients with idiopathic pericarditis and that, on the other hand, correctly identifies most cases of specific pericarditis, which mainly comprise purulent, tuberculous or neoplastic pericarditis. In accordance with this rationale and on the basis of our own experience, we have proposed a protocol for the management of acute pericardial disease that differs markedly from the "Guidelines on the Diagnosis and Management of Pericardial Disease" recently produced by the European Society of Cardiology. In addition, we have made some comments on the cardiac tamponade and the acute and subacute constrictive pericarditis that can occur during the resolution of acute pericarditis.