Cycling is one of the most sustainable modes of transportation. Increased ridership reduces fossil fuel consumption and pollution, saves space, and improves public health and safety. However, the bicycle itself has managed to elude environmental critique. Studies that calculate the environmental impact of cycling almost always compare it to driving, with predictable results: the bicycle is more sustainable than the car. Such research may encourage people to cycle more often but doesn't encourage manufacturers to make their bicycles as sustainable as possible.