Over the past 15 years, mechanical valves, and in particular, bileaflet mechanical valves, have made considerable strides in durability and hemodynamic per- formance. However, biocompatibility in terms of thrombo- embolism, thrombosis, and hemolysis has remained an area where improvement is needed. "New Development in Bileaflet Mechanical Heart Valve" discusses advances in these important areas of prosthetic valve function and provides clinical experience with a new open pivot, bileaflet mechanical valve.