Founded in 1988, Earth Share describes itself as "a nationwide network of America's leading non-profit environmental and conservation organizations" which "promote environmental education and charitable giving through workplace giving campaigns." Its key interests include "global warming, protecting ancient forests, protecting our water from toxic contaminants, and saving endangered species." Toward those ends, Earth Share supports radical environmental organizations claiming to share those same priorities. These recipients of Earth Share's support are all national or international in their scope. Earth Share's eligibility criteria stipulates that each of its member organizations must have conducted programs in at least 15 states or one foreign country. In Earth Share's payroll contribution drives, employees can pledge a designated amount of each paycheck to the Earth Share member organization(s) of their choice.   

Hundreds of workplaces across the United States currently participate in Earth Share's fundraising campaigns. Among these are such corporate giants as American Airlines, Dell, American Express, Hewlett Packard, NOKIA, and many more.

In summer 2005, Earth Share released a number of radio Public Service Announcements (PSAs), recorded by actress Patricia Clarkson, "on the alleged impact of environmentally induced health threats to America's children. The ads identify these threats as "pesticides and other toxins that may be found in schools," "mercury in our food chain," and the "childhood obesity epidemic." Created and produced by Earth Share's pro bono ad agency, Foote, Cone & Belding-Chicago, such PSAs have been distributed to thousands of media outlets each year since 1992.

As of May 2006, Earth Share's PSA campaign had received more than $505 million in donated media since its inception. Earth Share ads have been granted donated space in CNN, NBC, CBS, Sports Illustrated, U.S. News & World Report, Popular Science, Cosmopolitan, People, InStyle, The New Yorker, Entertainment Weekly, Time, The New York Times, and many other publications and broadcast stations.

Earth Share's Executive Vice President is Renny Perdue, who previously spent spent 18 years working with Mobil Corporation.
 
As of May 2006, Earth Share had 39 national member organizations, including: Defenders of Wildlife; Earth Day Network; Environmental Defense; Friends of the Earth; the Izaak Walton League of America; the National Wildlife Federation; the Natural Resources Defense Council; the Nature Conservancy; the Rainforest Alliance; Trust for Public Land; the Union of Concerned Scientists; the U.S. PIRG Education Fund; the Wilderness Society; and the World Wildlife Fund.