1. A method for performing access control decisions, comprising: specifying a protected object namespace based on a Web Service Description Language (WSDL) document such that a Web Services Addressing-defined endpoint reference provides a reference into the protected object namespace, wherein the protected object namespace is based on an abstract part of the WSDL document, the WSDL document also including a concrete part that is based on the Web Services Addressing-defined endpoint reference, wherein the abstract part is adapted to be used for authorization decisions for multiple, distinct concrete bindings of the WSDL document, wherein first and second concrete bindings are each based on distinct Web Services Addressing-defined endpoint references; de-referencing the Web Services Addressing-defined endpoint reference into a pointer into the protected object namespace; and using a computing device having a hardware processor to perform an access control decision with respect to a resource using one of a set of authorization mechanisms represented by the pointer into the protected object namespace.