Several cities around the world have introduced congestion charging schemes. Drivers are expected to pay a fee in order to drive inside the charging zone. In recent years, some schemes have offered discounts or entirely waived the charge for vehicles that cause less pollution. This is, however, an illogical and unfair policy that should not continue. Congestion is unaffected by emissions, and those cars that have low emissions still contribute to congestion. Those who cannot afford to buy a low-emission car are still expected to pay the charge even if the roads they drive on remain congested.