An analysis showing that the natural satellite Phobos might well be used as a terminal for a scientific Mars expedition, before manned landing on Mars is attempted. It is also shown that achievement of a self-contained-base capability as early as possible and the ability to extract water from rocks could lead, within present technology, to production of cryogenic hydrogen and oxygen on Phobos and Mars. This would relieve the need to transport fuels for return flights to earth or its satellite. With the reduction in logistics requirements, return cargoes could be brought to the earth. The study of these approaches may lead to earlier planetary exploration and utilization of Mars than could be expected by waiting for the availability of nuclear or ion propulsion systems. 53 pp.