Gage was the Chief Researcher and Director of the Science Office for Sun Microsystems, Inc, and a partner in the venture capital firm Kleiner, Perkins, Caufield and Byers.

Gage attended the University of California, Berkeley, the Harvard Kennedy School of Government, and the Harvard Business School. He did doctoral work in mathematics and economics at the University of California, Berkeley, and left Berkeley in 1982 to join Bill Joy as one of the original employees of Sun Microsystems.

Gage has served on scientific advisory panels for the US National Research Council and the National Academy of Sciences. He served on the Markle Task Force on National Security, whose reports helped reorganize US intelligence and security agencies. He most recently served on the US National Academy of Sciences Committee on Scientific Communication and National Security, whose report, “Beyond Fortress America: National Security Controls on Science and Technology in a Globalized World” was published in 2009.

He has been a member of the Board of Regents of the US National Library of Medicine, the Board of Trustees of Fermi National Laboratory, the External Advisory Council for the World Bank, the Board of Trustees of the Internet Society (ISOC), and the Board of the Pardee RAND Graduate School of Public Policy.

He created NetDay, the first mass movement organized on the Internet, which mobilized hundreds of thousands of parents and engineers to install Ethernet networks in US schools. In 1995, using meter-accurate maps of 140,000 US K-12 schools, he pioneered the use of the Internet for completely decentralized self-organization. NetDays spread to Korea, Malaysia, the UK, France and other countries. Gage received the ACM President’s Special Award in 1998 for connecting millions of children to the Internet.

He was a fellow of the Harvard Kennedy School of Government’s Shorenstein Center, and taught a course on technology, media, and governance in Fall, 2000.

He is on the Board of the Tegla Lorouope Peace Foundation, working to bring peace and economic development to the nomadic tribes of the Rift Valley of Kenya.

He is on the Board of Relief International, the Oxford James Martin School for the 21st Century, the University of California, Berkeley Goldman School of Public Policy, the University of California, Berkeley Library, and the World-Wide Web Foundation.

He is on the Advisory Boards of Neofocal, a semiconductor company fabricating controls for LED lighting, and Liquid Robotics, creator of autonomous ocean vehicles powered by wave action.

Gage lives in Berkeley with his wife Linda, and their two children, Peter and Kate.