As the next significant software abstraction, software agents have generated lots of excitements in recent years because of its promise as a new paradigm for conceptualizing, designing, and implementing software systems. This promise is particularly attractive for creating software that operates in environments that are distributed, open, and complex, such as the Internet. The effort of developing agent systems have, however, suffered from lack of generalized agent architecture because of various properties of an agent and nonexistence of a standard agent architecture. An agent architecture is an important criterion in order to not only identify agents in their domain but also determine the software architecture of the system. The major contribution of the work described here is an object-oriented design of an agent architecture that addresses fundamental properties, which are autonomy and interaction. Object-oriented design method is used for identifying the internal modules of an agent architecture and organizing correlation between the modules are identified.