Since 1959 the authors experienced 43 cases of chronic constrictive pericarditis treated surgically at the Department of Thoracic & Cardiovascular Surgery, the National Medical Center in Seoul. Of 43 cases, detailed patients` records could be obtainable in 36 cases, and most of our studies, were made on the basis of these 36 available cases. About 84 per cent of the cases were male with several pediatric cases, and duration of symptoms ranged between 2 months and 10 years. The diagnosis of this condition is not difficult, however, about half of our cases were previously treated under the impression of various other conditions such as liver cirrhosis or nephrotic syndrome at other hospitals and clinics. Many of our cases showed hepatic functional disturbances and about 89 per cent of the cases showed reversed A/G ratio, and we are sure that some of them had so-called protein losing enteropathy. Three of 36 cases showed normal electrocardiogram, and most peculiar electrocardiographic findings were ST or T changes and low amplitude of QRS complexes. Seven cases showed uricular`fibrillation and five had first degree A-V block. Mean preoperative peripheral venous pressure at the antecubital fossa and arm-to-tongue circulation time were 273 mm H2O and 20.2 seconds, respectively, and they were markedly reduced post-operatively to 152 mm H2O and 13 seconds, respectively. Several different approaches were made with various extents of pericardial decortication according to patients` condition and probably surgeon`s preference. In 12 cases we met cardiovascular injuries during decortication and one of them died of massive bleeding through the torn right atrium, and we experienced excellent postoperative result in a grave case operated on just a small pericardial window. Eleven of 35 cases were tuberculous pericarditis and others were non-specific pericarditis hist-opathologically, and 6 of total 43 cases operated on passed away by various ways with the mortality rate of 13.9 per cent.[KTCS 1975;1:101-108]