Pulmonary embolism is a common disease in the United States, affecting as many as 500,000 persons annually. Unfortunately, this disorder is commonly undiagnosed, resulting in significant excess morbidity and mortality. The clinical symptoms and signs caused by pulmonary embolism are nonspecific and may be confused with a variety of other cardiopulmonary disorders having similar presentations. However, accurate diagnostic tests are available for diagnosing pulmonary embolism, even in the face of coexistent cardiopulmonary disorders. This article describes the clinical characteristics of pulmonary venous thromboembolism, reviewing its typical symptoms and signs, its routine laboratory tests, and chest radiographic abnormalities.