Another tool in the engineer tool belt is the trade study. Need a decision among many alternatives? Do a trade study. The hardest part, what criteria to use. For instance, looking for the best car for the environment? Well you want to look a gas mileage, fuel used, and emissions emitted. But here's a trade study which took a more holistic view by taking into account the environmental impact of the cars production and most importantly, DISPOSAL. The winner: The Hummer. Controversial but true. Trade Studies, specially a 479 page report, can't lie. Can it?