The goal of the Climate CoLab is to harness the collective intelligence of thousands of people from all around the world to address global climate change. Inspired by systems like Wikipedia and Linux, the Massachusetts Institute of Technology (MIT) Center for Collective Intelligence has developed this crowdsourcing platform where citizens work with experts and each other to create, analyze, and select detailed proposals for what to do about climate change. Anyone can join the Climate CoLab community and participate. Community members are invited to submit and comment on proposals outlining what they think should be done about climate change. By constructively engaging a broad range of scientists, policy makers, business people, investors, and concerned citizens, we hope the Climate CoLab will help to develop, and gain support for, climate change plans that are better than any that would have otherwise been developed.