The Rocinha favela in Rio de Janeiro is paradigmatic of the socio-economic and environmental contradictions of the Brazilian mega-city, but is also a significant case study for slum-upgrading programs. PolimiparaRocinha, that is a research project developed in the framework of Polisocial (the social responsibility program of the Politecnico di Milano), provides a multidisciplinary methodology integrating environmental expertise, urban design and energy efficiency with water and waste treatment strategies in a systemic approach. The research aims to understand if the optimization of environmental performances, correlated with a bottomup and demand-driven approach, can improve the favela’s living conditions.