Subxiphoid pericardiostomy for diagnosis and treatment of pericardial effusion was used in 21 patients. Total evacuation of the pericardial contents, direct inspection to break down loculations, simultaneous biopsies of the pericardium and pericardial fluid samples for diagnostic tests were achieved while avoiding the need for repeated pericardiocentesis and more invasive and difficult open drainage methods. Complete drainage without recurrence was obtained in 19 patients with one death and recurrence of effusion in another one. Two of these 19 cases developed constrictive pericarditis on follow-up and required a pericardiectomy. No other complications were encountered. The procedure can be done safely under local anaesthesia for all types of pericardial effusions providing prompt and long term relief of the abnormal haemodynamics.