The GREAT project, funded by the UKRI Global Challenges Research Fund, sought to understand the ways in which being on- and off-grid provide an opportunity to rethink the relationship between people and urban infrastructure in areas of transition. Bringing together expertise across the environmental sciences, transport and geomatics engineering, design, architecture, urban planning, entrepreneurship, sociology, and history, we successfully embedded the voices and visions of residents of informal settlements in the plans for the futures of Cali and Havana.