Pulmonary thromboembolism (PTE) is a common and potentially serious disorder, characterised by highly variable clinical presentation, which makes it difficult to diagnose. Early estimation of severity is important to adjust the diagnostic process appropriately to manage the condition. In addition, the clinical likelihood of PTE should be considered, and laboratory tests (especially D-dimer) and imaging (echocardiogram, CT angiography) should not delay the start of emergency treatment. Treatment should be supportive, based on resolving vascular obstruction by fibrinolysis or anticoagulation, depending on the patient's clinical profile and situation, and on preventing recurrence.