At the 2011 meeting of the UN General Assembly, the governments of eight nations-Brazil, Indonesia, Mexico, Norway, Philippines, South Africa, the United Kingdom, and the United States-launched the Open Government Partnership, a multilateral initiative aimed at promoting transparency, empowering citizens, fighting corruption, and harnessing new technologies to strengthen governance. At the time, many were concerned that the Open Government Partnership would end up toothless, offering only lip service to vague ideals and misguided cyber-optimism. The Power of Partnership in Open Government offers a close look, and a surprising affirmation, of the Open Government Partnership as an example of a successful transnational multistakeholder initiative that has indeed impacted policy and helped to produce progressive reform.