Mitral insufficiency (MI) accounts for 24% of adult valvulopathies and affects 7% of subjects older than 75 years. They are the second leading cause of valvulopathy in Europe. The most common etiology is the associated valvular prolapse. Mitral surgery remains the reference treatment for symptomatic MI. The success of this procedure depends on the mitral valve geometry and the location of the prolapse. The site of the prolapse, whether monovalvular, localized to the posterior or anterior leaflet, or bivalvular, influences the possibilities and probably the long-term results of the plasty.