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.

American National Election Studies produces high quality data from its own surveys on voting, public opinion, and political participation.

Bob Stallman is president of the American Farm Bureau Federation. The national organization links to state farm bureaus. See its backgrounder (PDF) on the bill and an explanation of its priorities and concerns about the Senate measure.

Jon Scholl is president of American Farmland Trust, a conservation organization. It has a website devoted to the farm bill.