Distributed computing, where the underlying network is complex, heterogeneous and un-reliable, is hard to realize with traditional approaches. Energy Distribution Automation (DA), where the power line is used for communication, and the processing is highly distributed, is our application domain for assessments of new technologies for this kind of system. In this paper we propose a Multi-Agent approach with a large expected number of heavily distributed, medium grain agents. The concept of Agent-Oriented Programming (AOP) is adopted, and an architecture, the DA-SoC, is developed. The language DAAL is used for pro-gramming the agents, and the most important feature is a novel programmable Model of Inter-action (MoI), which allows the user to tailor agent interaction and the social behaviour of agents in the society. The semantic addressing is a powerful abstraction mechanism, that facilitates run-time network management. The emphasis of the paper is on describing and analysing the architecture, the language and the programmable MoI. An example from the DA application domain illustrates how the DA-SoC can be used. The research reported here is a cooperation between the authors’ affiliations mentioned above, and it is a part of the larger projects, Intelligent Distribution Automation (IDA) at Syd-kraft, Malmoe, Sweden, and Societies of Computation (SoC) at the University of Karlskrona/Ronneby, Sweden.