The global scenario put together by communication networks determines new opportunities towards the realization of Internetbased distributed services in many complex and composite application areas, such as the access to museum information. Solution complexity mainly stems from the heterogeneous representation formats of data, their geographical distribution, the large number of data sources involved, and the user requirements for personal customization and optimization of the accessed services. The paper claims that the realization of flexible museum information access services require a middleware-level approach and the implementation of a distributed support infrastructure. Within the MOSAICO project, we have realized the VM (Virtual Museum) framework on top of the SOMA (Secure and Open Mobile Agent) programming environment. Mobile agents have been chosen for their intrinsic properties of autonomy, asynchronicity, dynamicity of distribution, and adaptability to available system res...