Dr. Hans Herren at the Rio+20 conference on sustainable development, which took place in Rio de Janeiro, Brazil in June 2012 and was the biggest UN conference...

David Suzuki at the Rio+20 conference on sustainable development, which took place in Rio de Janeiro, Brazil in June 2012 and was the biggest UN conference...

Vandana Shiva at the Rio+20 conference on sustainable development, which took place in Rio de Janeiro, Brazil in June 2012 was the biggest UN conference...

The Rio+20 conference on sustainable development, which took place in Rio de Janeiro, Brazil in June 2012 was the biggest UN conference ever.  Was it...

The Rio+20 conference on sustainable development, which took place in Rio de Janeiro, Brazil in June 2012 was the biggest UN conference ever.  Was it...

The Rio+20 conference on sustainable development, which took place in Rio de Janeiro, Brazil in June 2012 was the biggest UN conference ever.  Was it...