Where there is concrete, let there be colour; where there is asphalt, let there be kickass graffiti. The world’s metropolises are grey enough places without a hard line stance against good graffiti. Take Sao Paulo, whose sprawling mass is home to almost 20 million people. When street art duo 6EMEIA...This is just a brief summary, please visit Environmental Graffiti to see the full, formatted version of the article