The Mars Society of Canada and the Mars Society Australia have launched this joint venture to concentrate of many aspects of Mars analogue studies. These include: geology, biology, field science operations, comparative spacesuit studies, field data logging, rover operations research, crew interaction, and crew member cognitive function. Expedition One takes the researches of previous missions to a new level though careful preplanning and integration of research goals in a four-phase program. A large team of 26 people will rotate through the hab to carry out the integrated program with 14 researchers in residence at any one time. Expedion One will culminate in a final 6-day phase of of high simulation fidelity with a 7 person crew in residence and 3 others away from the hab on a 5 day rover traverse which will also be carried out under strict simulation conditions.