This chapter discusses the vascular emergencies, which includes pulmonary embolism (PE), aortic dissection, and acute limb ischemia. PE is an important cause of morbidity and mortality among hospitalized patients. Goals of PE management include prevention of death from the current embolic event, to reduce the chances of recurrent embolic events and to minimize long term morbidity due to the event. Acute aortic dissection is the most common catastrophic event affecting the aorta, with an estimated annual incidence of 5–30 per million. Dissection of the aorta is characterized by separation of the layers of the aortic wall, due to blood entering through a tear in the intimal layer. Acute limb ischemia is a serious medical condition characterized by a rapid decrease in limb perfusion. It usually produces new or worsening symptoms or signs, and often threatens limb viability. Outcomes and prognosis of acute limb ischemia largely depend on the rapid diagnosis and initiation of appropriate and effective therapy. A detailed discussion on venous thromboembolic disorders and investigations for deep venous thrombosis has been also provided in this chapter.