The purpose of this chapter is to familiarize the reader with the echocardiography in life-threatening conditions. After reading this chapter you will able to know echocardiography in chest trauma, blunt chest trauma, penetrating chest trauma, acute mitral regurgitation, acute severe aortic regurgitation, aortic dissection, Debakey classification, Stanford classification, pulmonary thromboembolic disease, air embolism, hypovolemia, large intracardiac thrombus. Liberal use of 24 illustrative labelled screen images and tables are intended to orient the reader as well as provide an example of the anatomical defect or finding being discussed for better understanding. There are tables in this chapter which are very well explained for studies with perioperative indications for use of transesophageal echocardiogram in trauma patients, classification of severe mitral regurgitation, Classification of severe aortic regurgitation, Standard two-dimensional transthoracic views in evaluating aortic dissection and conclusion of the chapter is also given at the end. There are 47 references given at the end of the chapter to facilitate further reading.