Enormous strides in diagnosis and management have allowed many patients with congenital heart disease to reach adulthood. Proper care of these individuals requires knowledge of the anatomic and hemodynamic faults of the original defect, the dynamic changes that occur with time, and the effects of adult diseases or surgical intervention on that physiology. Echocardiographic and Doppler assessment of these patients has revolutionized their management. This article has discussed individual abnormalities such as shunts, obstructive or regurgitant lesions, and great-vessel and chamber malpositions, as well as selective aspects of more complex malformations. In the patient with congenital heart disease, whether unoperated or postoperative, a complete echo-Doppler examination includes complete anatomic delineation of intra- and extracardiac structures using combined two-dimensional and color-flow imaging, assessment of chamber sizes and myocardial function, and complementary pulsed and continuous-wave Doppler and color-flow imaging to search for and quantitate valvular, subvalvular or supravalvular stenosis or regurgitation; extra- and intracardiac conduit stenosis; pulmonary and systemic venous obstruction; transseptal or patch shunts; and intracardiac hemodynamics.