This study emphasizes several factors that were of value in the diagnosis, prognosis, and treatment of a series of 200 patients with penetrating wounds of the pericardium or its contents. Cardiorrhaphy was performed in 187 cases, and pericardicentesis was used mainly as a diagnostic and temporary therapeutic measure. The individual physical signs that make up Beck's triad had limited diagnostic value, but did correlate somewhat with prognosis. Twenty-two deaths were related primarily to bleeding, five to myocardial infarctions from lacerated coronary arteries, and nine to a combination of bleeding, tamponade, and/or infarction. Because of the great importance of bleeding as a cause of death, cardiorrhaphy should be rapidly performed on all patients except those who achieve and maintain normal vital signs after pericardicentesis, with minimal or no blood replacement.