Negotiations by the world leaders at the COP21 summit should be guided by California’s experience. California’s climate efforts stem largely from its goal to reduce greenhouse gas emissions to 1990 levels by 2020, and then decrease emissions 80 percent below 1990 levels by 2050. This paper describes how performance standards and carbon pricing mechanisms have helped the state reduce emissions and increase renewable energy while creating economic growth, putting the state well on its way to achieving its emissions goals.