Upper-extremity deep vein thrombosis is a rare manifestation of venous thromboembolic disease. In the past few decades, the clinical importance of upper-extremity deep vein thrombosis has increased because of the wider use of central venous catheters and the development of ultrasonography as a simple and accurate objective diagnostic method. Primary upper-extremity deep vein thrombosis is a rare disorder (2 per 100,000 persons per year), which comprises (1) Paget-Schroetter Syndrome, also known as effort thrombosis, and (2) idiopathic upper-extremity deep vein thrombosis. Secundary upper-extremity deep vein thrombosis develops in patients with upper extremity central venous catheters, pacemakers or cancer and accounts for most cases of upper-extremity deep vein thrombosis. The imaging modes used for diagnosis are: duplex ultrasound, magnetic resonance. Contrast venogram is the standard diagnostic test for characterization of the anatomy. A staged, multimodal approach to Paget-Schroetter Syndrome can effectively restore venous patency, reduce the risk of rethrombosis, and return the patient to normal function. Primary care physicians should be aware of this condition and its atypical presentations, because delayed recognition in a high-functioning persons can be potentially disabling.