KLM has almost turned fuel-saving into a culture: since 2003 an increasing part of its entire organisation has been involved in decreasing kerosene consumption. This in order to save both costs and climate, as burning up one kilo of jet fuel creates 3.2 kilo CO2. There is a lot at stake. The 214-strong fleet of KLM and its subsidiaries used up over 3.5 million tons of jet fuel in 2008. The resulting bill was over €2bn, which accounts for almost one-third of the air carrier’s total operational costs. In KLM’s broad approach towards fuel-saving, statistics and optimisation of routes and fleet are the key words in a continuing process, focused at increasing the company’s competitiveness. By paying attention to every detail within its flight operations, KLM tries to predict the amount of fuel needed for every flight as accurately as possible.