Abstract The United Nations estimates that 3 billion people living in urban contexts will need adequate and affordable housing by 2030. We urgently need alternative perspectives and methodologies for urban development that are environmentally sustainable and inclusive of the local community. This chapter illustrates the design and results of projects carried out by YouthMappers in Rwanda, Italy, and Kenya, focused on informal settlements in the Global South and the value of geospatial data for addressing SDG 1 No Poverty and SDG 11 Sustainable Cities and Communities.