Various schools, collectives, and governments use architecture, art, and design to help poor communities of the global South improving their material environment. In this, macro-murals represent one of the most ambitious and visible forms. The lecture attempts to introduce the macro-murals as a new research field and to show how they are assembled through the complex socio-material relations. Based on reflections on fieldwork in Colombian cities, the lecture will discuss several topics pertaining to macro-murals: various definitions that enable us to understand this socio-material practice, the role of mobility of ideas, and impact on local communities. Instead of providing final definitions or results, this talk seeks to re-envision the topic and to embrace my developments and changing ways of thinking about the macro-murals and the conditions that have led to it.