Computerized control systems have been used in many years to supervise and control power distribution. These systems, which often are referred to as SCADA (Supervisory Control And Data Acquisition) systems, have in recent been more and more interconnected to other systems in recent years. In modern utilities various kinds of data are exchanged between the distribution management systems and the administrative systems located in the office network. For example are operational statistics, trouble reports and switch orders often communicated between the office systems and the systems inside the control center. This paper desccribes a survey over state-of-practice architectures in electrical distribution utilities. A set of system-services have been identified together with the interfaces that typically exists between these services. How these services are located within different zones within utilities is also identified. The set services, the data flows, and the location of these has been reviewed and validated by vendors of SCADA systems in the electric utility industry.