Can Collective Intelligence be used to produce social innovation? The advance of information andcommunication technologies in the 21st century seems to have unlocked the potential of collective intelligence, enabling us to mobilize large crowds to solve problems and produce novelty. However, despite early optimism, more recent scholarship suggests that collective intelligence has serious limits and in particular that it is not suitable for dealing with the types of complex problems that social innovators inevitably face. In order to evaluate more carefully the potential of collective intelligence to support social innovation I present a framework for looking at social innovation processes as a number of distinct phases and mechanisms. I then look at three examples of different types of online platforms used to mobilize collective intelligence. My analysis suggests that each of these has some capacity to support some elements of a social innovation process, but that as the theoretical literature would suggest none of them are useful throughout the process. However,since each of these different platforms has different strengths and weaknesses, by linking them together and utilizing the right platform at the right time, we may be able to harness collective intelligence to greatly enhance social innovation capacity.