Renewable energy, unusual transport networks, zero waste targets, organic farming and food, national reserves: the measures taken to protect the environment are diverse and varied. We travel the planet to explore the latest ideas from those countries seen as most virtuous in terms of good "green" practice.

Marked by major disparities between the producing countries in the South and the consuming countries, mostly in the North, the cocoa trade couldn't be more asymmetric. Are things finally about to change? We look at the initiatives launched by the African countries, with a helping hand from China.

The height of summer 2011. Two amateur sailors off the coast of Lorient spotted a large suitcase floating in front of them. As they came nearer, they saw a human foot protruding from it. Thus began an incredible investigation with just one clue: a key found in a pocket.