MSFC Director Wernher von Braun described to Apollo Spacecraft Program Manager Joseph F. Shea a possible extension of Apollo systems to permit more extensive exploration of the lunar surface. Huntsville's concept, called the Integrated Lunar Exploration System, involved a dual Saturn V mission (with rendezvous in lunar orbit) to deliver an integrated lunar taxi/shelter spacecraft to the Moon's surface.

Wernher von Braun stated that, though this concept was most preliminary, such a vehicle could bridge the gap between present Apollo capabilities and the longer term goal of permanent lunar bases. (Although this suggestion never found serious favor elsewhere within the agency, such thinking and ideas were indicative of speculation throughout NASA generally regarding possible applications of Apollo hardware to achieve other space goals once the paramount goal of a lunar landing was achieved.)