For many fine ideas and critiques, we thank our advisory group at Michigan State University, Roy Black, Kimberley Chung, David Connor, John Kerr and Patricia Norris. We also thank our external advisory group: Frank Casey (Defenders of Wildlife), Tim Dalton (U. Maine), Tom Dobbs (S. Dakota State U.), Michael Duffy (Iowa State U.), Sarah Lynch (World Wildlife Fund), Kent Olson (U. Minnesota), George Norton (Virginia Tech U.), Marc Ribaudo (USDA), Alfons Weersink (U. Guelph), Ada Wossink (North Carolina State U.), and David Zilberman (U. California-Berkeley).