The next years will be characterized by high levels of heterogeneity and interactions among devices connected to global networks. The first researches involving wide-area distributed systems answered many questions concerning resource management, although they fail in treating questions related to heterogeneity and dynamic adaptation. More recent works, through technologies like CORBA and Java/Jini, deal with heterogeneity problem, but do not deepen into adaptability aspects. In this article, we present the ISAM architecture. ISAM 1 is a middleware directed to resource management in heterogeneous networks, supporting physical and logical mobilities, dynamic adaptation and the execution of distributed mobile applications based on components. In order to achieve its goal, ISAM uses, as strategy, an integrated environment that: (a) provides a programming paradigm and its execution environment; (b) handles the adaptation process through a multilevel collaborative model, in which both the system and the application contribute.