The Mars Society is a U.S. registered non-profit organization that leads a worldwide movement, with dozens of chapters, to educate and inform the general public, members of the media, and government representatives about the importance of Mars exploration and the establishment of a permanent human presence on the Red Planet. Inspired by "The Case for Mars" conferences, which were hosted by The Mars Underground at the University of Colorado Boulder, the Mars Society was established by Robert Zubrin and others in 1998 with the goal of educating the public, the media and government on the benefits of exploring Mars, the importance of planning for a humans-to-Mars mission in the coming decades and the need to create a long-term human presence on the Red Planet.
Mars Society, Inc. was formally established in September 1997 under the Colorado Non-Profit Corporation Act. In August 1998 more than 700 delegates – astronomers, scientists, engineers, astronauts, entrepreneurs, educators, students and space enthusiasts – attended a week-end of talks and presentations from leading Mars exploration advocates. Since then, the Mars Society, guided by its steering committee, has grown to over 5,000 members and some 6,000 associate supporters across more than 50 countries around the world. Members of the Mars Society are from all walks of life and actively work to promote the ideals of space exploration and the opportunities for exploring the Red Planet. In 2017 the Marspedia encyclopedia became an official project of the Mars Society.