Brett Silcox is the Associate Director of the National Space Society, the leading space advocacy group dedicated to the creation of a spacefaring civilization. Founded in 1974 by Apollo program leader Dr. Werner von Braun, NSS members promote change in social, technical, economic, and political conditions to advance the day when people will live and work in space. NSS has approximately 20,000 supporters and more than 70 chapters around the world.

Silcox focuses on outreach, educational projects, and working with the aerospace corporate community to increase the presence of the NSS worldwide. In addition to these, he works on expanding relationships with the members.

He co-directs operations for the annual International Space Development Conference, including the most successful to date the 25th annual ISDC, in Los Angeles in May 2006.

In November 2006 he was elected to the steering committee of the Space Exploration Alliance, an unprecedented partnership of the nation’s premier non-profit space organizations with a combined membership of more than 100,000 people throughout the United States, and became a member of the Washington Space Business Roundtable, the leadership forum for the promotion of commercial space business and education in the national capital region.

He was also a participant of the workshop, "Building and Maintaining the Constituency for a Long-Term Space Exploration," in 2006 that focused on maintaining the Vision for Space Exploration thru the next generation and was also a participant in NASA’s 2006 Industry Workshop for it’s Exploration Strategy Architecture.