Abstract: In multimedia systems that implement secure access techniques, a method and apparatus for a security policy and enforcing mechanism for a set-top box security processor are provided. A security policy may be determined for a multimedia terminal based on high-level requirements by various system users. A default mode of operation may be generated based on the security policy and may be stored in a security policy memory. An access control matrix that indicates the operation of security components in a security processor for various user modes may be stored in the security policy memory. Control and/or access operations not supported by the access control matrix may be supported by the default mode of operation. The user modes in the access control matrix may include composition user modes. Accessing the information in the security policy memory may be utilized to enforce the security policy in the multimedia terminal.