Memo for the Record, 30 October 1968a, Subj: Telephone conversation [on 29 October] with Col. Pullen, Hq SAC. SSO-SAC is the acronym for the Special Security Office at Strategic Air Command headquarters. Originally, the SSO was under the authority of the United States Air Force Security Service (a subsidiary to the National Security Agency), responsible for devising encrypted communications capabilities and providing security support to military commands and other organizations receiving intelligence and communications. In 1965, the SSO functions transferred to the major user commands (MAJCOM). Within the commands, the primary function of the SSO officer is the management of Special Access Programs (SAP), and Sensitive Compartmented Information (SCI), in which even the extra protection measures applied to Top Secret information are not sufficient. The term refers to a method of handling certain types of classified information that relate to specific national security topics or programs whose existence is not publicly acknowledged, or of a sensitive nature requiring special handling. These “need-to-know” classifications necessitate a special “SCI access,” or SAP approval, before anyone can gain access to this information. For additional information see: