Many adaptative context-aware middleware exist and most of them rely on so-called vertical architectures that offer a functional decomposition for contextawareness. This architecture has a weak point: it does not allow the system handling both dynamics of the changing environment and applications. To avoid this, we propose an approach for context-awareness based on a behavioral decomposition, and because each behavior must complete all functionalities necessary for contextawareness, we introduce an hybrid decomposition. It consists in a functional decomposition into a behavioral decomposition. This approach derives benefits from both decomposition, first allowing to handle environment and application's dynamics, second introducing reusability and modularity into behaviors.