In order to provide a clear and accurate understanding of the Accreditation and Certification of Information Security Management System (ISMS)-ISO17799/BS7799 to all organizations, this article is to introduce the relevant international organizations (Accreditation Body, Certification Body) and their interrelationship based on the structure of Accreditation system. Furthermore, this article also clarifies the registration process of Certification in anticipate to present a precise outline to those organizations with interest.