The paper seeks to define urban design in relation to the specific challenges of emerging cities. Through a case study of Mudo Coletivos temporary structure, Bolha Imobiliaria, and the making of it, I wish to outline a design approach for urban design in cities lacking public spaces. Urban design is understood in a broad sense, not as architectural design but as spatial design and artistic interventions in public space. Through the paper I will address how the designer can co-create and reassemble existing urban spaces through design acts. The approach suggests a situated design methodology but is based on a theoretical understanding. It is my belief that the designer, by looking into the emergent properties of urban spaces, instead of its physical and cartographical outlines, can see her work as a processual intervention in the city rather than durable object design.