Considerable etiologic factors may lead to the development of pathologic pericardial effusion. In many cases these factors remain unidentified, the fact which leads to difficulties in choosing the appropriate therapeutic strategy. The therapy of pericardial effusion associated with purulent pericarditis must be different than that effusion developed as a consequence of neoplasm or autoimmune disease. The cytological examination of the fluid and the hystological examination of the pericardial tissue play an important role in identifying the accurate etiologic diagnosis. In case of recurrent pericardial effusions, performing pericardioperitoneal, pericardiopleural shunt or pericardial window may be indicated. This palliative solution serves to prevent the development of pericardial tamponade and its haemodynamic consequences.