Environmental issues in China… it’s a hot topic. Every day there seems to be a new horror-story in the news about toxic farmland, contaminated rivers or smog-filled cities. But this urban art project, done by Jody Xiong of DDB China in conjunction with the China Environmental Protection Foundation, is something really positive that deserves to be highlighted too.
This wonderful outdoor campaign created a subtle visual reminder of the environmental benefits of walking versus driving. By walking, people literally made their environment greener. Enormous white canvases with a bare tree were placed across 7 crosswalks in Shanghai. As pedestrians crossed, their shoe soles were imprinted with a small amount of green ink, leaving behind a trail of leaf-like footprints. The final posters were eventually hung as billboards in several urban locations.
Involving random people this way, resulted in a very powerful campaign. Love it! (Via)
Studio Refill Ltd 
Simple idea but great execution! Loved the post.
Thanks Shruti;-). So simple and yet so powerful indeed. I totally agree with you!