Dutch artists Jeroen Koolhaas and Dre Urhahn (Haas and Hahn) have recently given Santa Marta, A favela in Rio de Janero, a colorful facelift. The application of color in this context makes an impressive impact on the neighborhood and darws attention to our physiological perception of color iwth -in our built environment. The artists furthered their impact by hiring local painters to install the mural to stimulate local employment. You can read more about Hass and Hahn here.