Abstract: With the purpose of effectively managing services within complex distributed environments, this paper first discusses several problems faced by traditional management approaches, and then presents a comprehensive conceptual model of service management with four dimensions: management function, layer, activity, and method. Based on the conceptual model, the paper introduces a practical agent based distributed service management model AADCS, which incorporates both primary and management functions into a unified computational framework and development process, enabling them to interoperate with each other equally and seamlessly. AADCS adopts a two dimensional domain model to layer and partition the entire system topology, and supports point to point centralized management and distributed management by delegation （MbD）, which can dynamically adjust resource allocation between primary and management functions. Development practice with AADCS has proved it an effective management model for complex network environment including Internet.