Possibiiitles to support openness in an environment of evolving. but not yet stabilized standards are discussed. The architecture of a workstation-based energy management system following the rules of open system architecture is detailed. Interutility communication using de facto standard protocols is outlined. An example of functlon distribution to lndlvidual servers Is given. Experience with the Introducllon of dlslrlbuted energy management systems Is reported, Applications of multiprocessor workstations and the effect of Intelligent substation equlpment on control centre functions are discussed. Back-up possibilities of control centers are investigated. Benefits of utility-wlde access IO selected EMS data are shown.