This chapter tells how to do 3D transthoracic echocardiography examination. This chapter exciting goal is the renewal of patho­physiological insight through this 3D imaging of cardiac structures and function which should pave the way toward new research in cardiology. History of 3DTT echo, methods for data acquisition, left ventricular assessment, reproducibility, regional LV function, aortic regurgitation, aortic annulus, mitral stenosis, mitral regurgitation, tricuspid valve disease, pulmonic valve disease, advances in pediatric and fetal cardiac pathologies are described in detail. Studies issued from research on animals are voluntarily excluded from this chapter for ethical reasons. 29 comprehensive and self-explanatory echocardiac images are included in this chapter. The 99 references mainly list the studies with the most recent generation of transducers are given at the end of the chapter to facilitate further reading.