Abstract. The explosive evolution of pervasive computing environments presents several new challenges such as smart spaces, invisibility, localized scalability, and masking uneven conditioning. One of the key challenges in such environments is how to manage security and access control. A suitable approach for managing access control in pervasive computing environments should consider different features of such environment which are not supported by traditional access control mechanisms. The features impose the access control mechanisms to satisfy especial requirements. In this paper, we propose an access control framework supporting different requirements of pervasive computing technology. The framework is capable of providing solutions to the requirements by some functionalities such as decision making based on user intent and in an invisible manner and reauthorization of granted services based on context changes. KEYWORDS--Access Control, Security Framework, Pervasive Computing.