With fuel shortages projected into the future and automotive industry trends continuing towards utilization of smaller gasoline, diesel, and turbocharged engines, many vehicle manufacturers recognize the desirability for eliminating vacuum powered and belt driven engine accessory attachments. A desirable goal becomes demand systems, which utilize or consume energy only when being operated, to replace many of the present day continuous running systems.As a building block for satisfying the above long term need, Bendix has developed a demand power brake system powered by a small electric motor. This paper will be directed primarily to the design and operating characteristics of this new power brake system that Bendix Automotive Control Systems Group of the Allied Corporation has named “Hydro-Electric Full Power”. The system is designed for use in most hydraulically actuated vehicle brake applications up to 4, 536.0 Kg (10,000 lbs.) GVW. The new system also simplifies integration of a hydraulic anti-skid system.