Environmentalists hold a banner at the entrance of the Brazil Pavilion for the Rio+20 United Nations sustainable development summit in Rio de Janeiro

 
Environmentalists hold a banner at the entrance of the Brazil Pavilion for the Rio+20 United Nations sustainable development summit in Rio de Janeiro
Environmentalists hold a banner at the entrance of the Brazil Pavilion for the Rio+20 United Nations Sustainable Development summit in Rio de Janeiro June 20, 2012. The Rio +20 United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Nacho Doce (BRAZIL - Tags: ENVIRONMENT SOCIETY POLITICS)