ADP Co-chairs Daniel Reifsnyder (left) and Ahmed Djoghlaf (center) say their negotiation work is difficult but worth it. "We only have one planet, you know," Reifsnyder says. "We have to protect it." Courtesy of IISD/ENB hide caption

itoggle caption Courtesy of IISD/ENB

Country representatives listen to opening remarks at the start of the United Nations' Conference of the Parties on Climate Change in Lima, Peru. Cris Bouroncle/AFP/Getty Images hide caption

itoggle caption Cris Bouroncle/AFP/Getty Images