As ever, the tricky bit is deciding which car to buy. You can't simply look at the headline CO2 figure, because cars emit a whole concoction of polluting gases that also need to be taken into consideration. You need to think about which cars are both good to drive and to live with, too.
That's why the What Car? Green Awards are essential reading for anyone with even half an eye on the environment. We reward cars that major on green credentials but don't require any compromise from you.
Take a look at the following pages for the best cars in each category and our overall winner.