Key findings || Reliable data and analysis are central to the achievement of global and regional development and humanitarian policy processes relevant to IDPs. Demands for systematic data collection, analysis and research have not however been matched by the political will and resources required to meet them. As a result, the current baseline and global picture of internal displacement are currently incomplete. || The time-series data needed to measure progress toward global targets is not collected through to the end of displacement. This means that we do not properly understand how different displacement situations and specific IDPs’ vulnerabilities evolve over time. Further gaps include limited geographical scope, exclusion of certain types of displacement, and disaggregation of data by age, sex, location, needs and vulnerabilities. 70 GRID 2017 || Without comparable data on different situations and how they have changed over time, there is little evidence to tell us what works. Yet this information is critical to remove the guesswork currently involved in humanitarian and development financing. New and innovative solutions need to be deployed to fill the data gaps and establish a more comprehensive picture of displacement. New “hybrid” approaches that combine event detection with the analysis of time-series data on evolving situations are essential. || Detecting incidents of new displacement needs to be scaled up significantly, employing semiautomated processes that monitor displacement associated with disasters, conflict, violence and development projects. For disasters, more timeseries data on people once they have become displaced is key in order to infer both the total number of people displaced by an event and to track the number and needs of displaced people as they evolve over time. In addition, more investment is needed in probabilistic risk modelling for disaster displacement in order to identify and address the drivers of displacement risk. Furthermore, the assessment of displacement risk and the factors that contribute to it should be extended to other contexts.