[en] The ESBWR plant design has evolved over the years to take full advantage of passive features. The main passive features are the use of natural circulation and safety features for decay heat removal and inventory control. The use of natural circulation has allowed the elimination of the recirculation pumps and their auxiliary support and control systems. Additionally, the use of natural circulation with its shorter core has allowed the reduction of the number of control blades and control rod drives and simplification in the reactor internals and vessel design. The use of passive safety systems has resulted in the elimination of many complex systems involving pumps, heat exchangers, diesel generators, intermediate cooling water systems and their associated piping and controls. The resulting safety systems are simple and compact and impose no significant challenge to the operator. Additionally, the use of passive features has resulted in improved plant performance and in many cases increased margins. (author)