Scope Associated with the provision and operation of a Trusted Third Party (TTP) are a number of security-related issues for which general guidance is necessary to assist business entities, developers and providers of systems and services, etc. This includes guidance on issues regarding the roles, positions and relationships of TTPs and the entities using TTP services, the generic security requirements, who should provide what type of security, what the possible security solutions are, and the operational use and management of TTP service security. This Recommendation | Technical Report provides guidance for the use and management of TTPs, a clear definition of the basic duties and services provided, their description and their purpose, and the roles and liabilities of TTPs and entities using their services. It is intended primarily for system managers, developers, TTP operators and enterprise users to select those TTP services needed for particular requirements, their subsequent management, use and operational deployment, and the establishment of a Security Policy within a TTP. It is not intended to be used as a basis for a formal assessment of a TTP or a comparison of TTPs. This Recommendation | Technical Report identifies different major categories of TTP services including: time stamping, non-repudiation, key management, certificate management, and electronic notary public. Each of these major categories consists of several services which logically belong together.