This chapter contains sections titled: Diagnosis of venous thromboembolism Therapeutic agents Initial treatment of venous thromboembolism Secondary prophylaxis Treatment of patients with cancer Venous thromboembolism in pregnancy The post‐thrombotic syndrome Diagnosis of venous thromboembolism Therapeutic agents Initial treatment of venous thromboembolism Secondary prophylaxis Treatment of patients with cancer Venous thromboembolism in pregnancy The post‐thrombotic syndrome