In developing countries, citizen engagement in the rapid growth and development that many cities are experiencing is not a priority. Even when city governments want to engage citizens, finding methods that effectively do this are often quite challenging. With “Block by Block”, United Nations Human Settlements Programme, and Mojang, makers of popular online game Minecraft, are exploring how the game could be used to find out how people want to see their cities develop in the future. Using the game, residents can build simple 3D models of their community. This is a simple and effective way to visualise future developments and create a consensus within the community. They first trialed Block by Block in Kibera, Nairobi’s largest slum, in 2012. Since then, they’ve started projects in nearly 30 other locations across the globe.