Evolving MDCT technology and high accuracy for pulmonary embolism detection has led to CT pulmonary angiography (CTPA) becoming a first-line imaging test. Rapid and accurate assessment for DVT and PE can be performed with a single test. Concerns remain regarding the radiation exposure incurred with CTPA and CT venography, especially in young patients. There are concerns also regarding radiation exposure in pregnancy and search for the best diagnostic test for PE in pregnancy. The increased detection of subsegmental emboli raises the question as to which emboli are significant and should be treated and which should be left alone. We review the current role of CT in the diagnosis of pulmonary embolism.