In 2017 several leading climate analysis organizations came together as part of the Mission 2020 campaign to define six milestones—in energy, transport, land use, industry, infrastructure, and finance—that would need to be met by 2020 to bend the curve in global greenhouse gas emissions and put the world on a pathway consistent with the Paris Agreement. To achieve each milestone, the organizations identified two or more outcomes, and this working paper takes stock of progress made toward those outcomes. One of the conculsions of this paper is: More transparent tracking of progress is needed across many areas. Greater transparency and monitoring systems will allow us to more accurately track progress across all of the sector milestones. Our ability to track progress toward these milestones is limited by data availability. In some cases, there are data lags that may not accurately capture the action on the ground today, and it can take time for recent commitments to take effect. Generally, the completeness and lag in available data may distort the current evaluation of progress. In other cases, insufficient data impede any endeavor to assess progress toward reaching some milestones. Efforts are needed to increase transparency and generate necessary data to hold countries, companies, and regions accountable to achieving any individual commitments they have made that contribute to the milestones. Establishment of tracking systems can bring significant benefits and help identify opportunities, adjust existing plans, and guide the adoption of new actions.