Transportation aspects of commercial spaceflight in the opening decades of the Twenty-first Century are envisioned. A specific Spaceliner concept is described, one predicated on combined-cycle airbreathing/rocket (“Synerjet”) propulsion. Its technical literature recorded heritage is reviewed. NASA's long-term goals, and its ongoing program relevant to this class of transportation concepts are discussed.A key observation, one of potentially distant, but great significance to the future of aviation and the air carrier industry, is that Spaceliner class systems, once available, can -- in addition to providing orbital payload service -- fly transglobally, conducting point-to-point terrestrial transportation services, all at ‘highest speed.” Providing an aviation/air-carrier perspective on all of this, in an annex paper attached, the candid views of an esteemed former airlines executive, the late Willis Player, are highlighted.Key Reference and Basic DefinitionsNote: A glossary of abbreviations is provided (p 14)Key Reference:SAE International Publication PT-54, ‘The Synerjet Engine, Airbreathing/Rocket Combined-Cycle Propulsion for Tomorrow's Space Transports,” compiled and edited by the author, 1997Key Definitions:Synerjet: A new kind of propulsion system in which advanced airbreathing and rocket propulsion technologies and selected hardware elements, are synergistically integrated to provide an efficient, lightweight engine. one capable of agilely Operating in multimode fashion over a very wide flight-speed and altitude range, in conducting both the ascent and descent phases of the overall mission profile.Spaceliner: A fully reusable, operationally dependable and highly affordable aerospace transportation vehicle powered by Synerjet engines. envisioned to become available in the early decades of the 21st Century.In brief, the future transatmospheric spacefaring counterpart of today's commercial transport aircraft.