While it may seem crazy to include a container ship company among a green list – said to contribute 4 percent of the world’s greenhouse emissions – Maersk deserves praise for reviewing its 2,000 suppliers and signing 1,500 of them up to its Responsible Procurement. In 2012 Maersk had already reached its 2020 target of reducing CO2 emissions by 25 percent per container from 2007 levels.