Five years after its launch, the Chicago Climate Exchange (CCX) is providing tangible evidence to U.S. lawmakers as to how a national carbon emissions trading program might work. How can the blueprint provided by CCX be applied to a national program? During today's OnPoint, Chicago Climate Exchange CEO Richard Sandor, discusses the lessons his organization has learned since its inception. Sandor explains the educational challenges ahead for legislators and he discusses the potential environmental and economic benefits of establishing a national carbon offsets market. He also responds to criticism of his organization's choice of offset projects.