This article is intended to provide surgeons and non-surgeons with a foundation of essential concepts and principles or the application of TEE in their practices. Included will be an overview of echocardiographic principles, advantages of TEE versus transthoracic echocardiography, comparisons of single-plane, biplane, and multiplane TEE, and how TEE can benefit general surgeons, trauma surgeons, and critical care surgeons in various clinical situations. A brief overview of basic echocardiographic images is provided.