The internet connects people who are spatially and temporally separated. One result is new modes of reaching out to, organizing and mobilizing people, including online activism. Internet platforms can be used to mobilize people around specific concerns, short-circuiting structures such as organizational hierarchies or elected officials. These online processes allow consumers and concerned citizens to voice their opinions, often to businesses, other times to civic groups or other authorities. Not surprisingly, this opportunity has encouraged a steady rise in specialized platforms dedicated to online petitioning; eg., Change.org, Care2 Petitions, MoveOn.org, etc. These platforms are open to everyone; any individual or group who is affected by a problem or disappointed with the status quo, can raise awareness for or against corporate or government policies. Such platforms can empower ordinary citizens to bring about social change, by leveraging support from the masses. In this sense, the platforms allow citizens to “crowdsource change”. In this paper, we offer a comparative analysis of the affordances of four online petitioning platforms, and use this analysis to propose ideas for design enhancements to online petitioning platforms.