Deep vein thrombosis and pulmonary embolism (DVT/PE) were first defined by Dr. Rudolph Virchow in the nineteenth century. This was the triad of inflammation of the vessel wall, venous stasis, and hypercoagulability which were the hallmarks for the pathogenesis of DVT/PE. Initially, the history and physical examination were the only methods of evaluation. Imaging for DVT/PE assessment evolved into venous duplex scanning, ventilation perfusion lung scanning, chest computed tomography, and chest MRI. The evolution of treatment of DVT/PE is reviewed to include heparin, low molecular weight heparin, direct oral anticoagulants, and thrombolytic therapy. These treatments evolved into catheter-directed therapies with thrombolytic agents or clot removal devices. This chapter provides a historical perspective of all the above areas of assessment and treatment of DVT/PE.