Launched by the World Wide Fund for Nature (WWF), the 'Earth Hour City Challenge 2015' contest is designed to recognise the cities most strongly committed to fighting climate change. The South Korean capital city, Seoul, was selected for this title from among 163 cities in 16 countries. A true role-model for sustainable development, Seoul has set the goal of reducing its greenhouse gas emissions by 10 million tons and attaining 20% electricity self-reliance by 2020. Seoul will host the next World Congress of Architects from 8 to 13 September 2017.