Open data—data accessed online for anyone to use and reuse—can improve the lives of people in the developing world. Open data enhances transparency, allowing citizens to participate more fully in the democratic process and hold their leaders to account. It also highlights inefficiencies and allows governments to tackle tough challenges more effectively.  Entrepreneurs also use open data to build new businesses. In order to realize these benefits, governments and other stakeholders must assess progress and gauge which models work best in different contexts. Measuring the supply, use, and impact of open data is an important step in meeting this objective. To address persistent knowledge gaps about the state of open data around the world, open data researchers have created a number of tools. The Open Data Barometer, produced by the World Wide Web Foundation, provides the most accurate assessment of open data in more than 90 countries around the world. It has become a key tool for reformers in government and civil society. Governments in the UK, Spain, South Korea, and Myanmar have improved their open data policies following recommendations from the Barometer. More recently, the Open Data Impact Map started to collect cases of open data use by the private sector around the world. This tool, developed by the Centre for Open Data Entreprise, shows that progress is still needed to put the power of data in the hands of citizens and to enhance innovation, accountability, and participation in developing countries. On the other hand, the impact map also demonstrates where leaders in government and civil society are taking action to harness open data for development, including adoption of the International Open Data Charter and the implementation of the sustainable development agenda in countries and cities. This project will support a new edition of the Open Data Barometer and improvements to the Open Data Impact Map. These tools will help advocates, policymakers, and researchers understand and ask questions about how the development of an open by default approach to government data is progressing. The project will also help to bring developing-country participants to the International Open Data Conference (IODC16) in Madrid in October 2016 to discuss these research activities as well as contribute to leading international initiatives on open data policy and standards.