Degenerative mitral valve disease has become the major cause of mitral regurgitation in North America; it is incumbent on surgeons to know repair techniques and to document their results. Fortunately, improvements in myocardial protection have been concurrent with the evolution of mitral valve repair in our country. The steep learning curve may be traversed, and the majority of degenerative mitral valves may be successfully repaired. Serial echo Doppler studies provide documentation of successful repair and monitor the patient's progress objectively. Echocardiography also provides a forum for communication between surgeons and cardiologists and, for the first time, the presence and amount of residual mitral regurgitation can be quantitated.