Thrombosis refers to the formation of blood clots in the blood vessels, i.e, veins and arteries. Venous thrombosis refers to the formation of blood clots in veins whereas arterial thrombosis refers to condition when blood clots block an artery. Thrombosis may be caused due to factors such as surgical procedures, immobility, inherited predisposition to blood clots, use of oral contraceptives, and underlying health conditions. Medical conditions such as cancer, pregnancy, inflammatory bowel disease, obesity, and certain rheumatic diseases can increase the risk of venous thrombosis. Deep vein thrombosis (DVT) and superficial venous thrombosis are the two common forms of venous thrombosis. DVT is a condition that leads to the formation of blood clots in the veins located deep in the human body. Some common tests for diagnosing venous thrombosis are duplex venous ultrasound, venography, magnetic resonance imaging (MRI), and computed tomography (CT) scan. The main treatment for venous thrombosis is anti-coagulant medication that helps to control the formation of blood clots in the body. This book provides significant insights into venous thrombosis. It consists of contributions made by international experts. Those in search of information to further their knowledge will be greatly assisted by this book.