Bill Ayres is executive director of WhyHunger, which works to battle poverty and hunger in the U.S. and abroad. It posts resources on the Food and Farm Bill.

Helene Murray is executive director of the Minnesota Institute for Sustainable Agriculture. It is a partnership among the University of Minnesota’s College of Food, Agriculture and Natural Resource Sciences, the University of Minnesota Extension and the Sustainers’ Coalition.

Mark Rasmussen is director of the Leopold Center for Sustainable Agriculture at Iowa State University.

Mary Hendrickson is associate director of the Community Food Systems and Sustainable Agriculture Program at the University of Missouri.

The Sustainable Agriculture Research and Education Program at the University of California-Davis provides research and education about agriculture and food systems. It posts a page explaining what sustainable agriculture is and what issues are involved.

Mark Bomford is director of the Yale Sustainable Food Project at Yale University in New Haven, Conn. It supervises a sustainable dining program at Yale, manages an organic farm and sponsors programs on food and agriculture.

Ferd Hoefner is policy director of the National Sustainable Agriculture Coalition, an alliance of several organizations.

Rob Hedberg is director of the Sustainable Agriculture Research & Education program, which is part of the U.S. Department of Agriculture’s Cooperative State Research, Education and Extension Service. It promotes farming systems that are “profitable, environmentally sound and good for communities through a nationwide research and education grants program.”

The Roper Center for Public Opinion Research at the University of Connecticut is one of the world’s leading archives of social science data, specializing in data from surveys of public opinion.