Its not a trade-off It used to be that big cars were safer while small cars were more economical. Thats no longer the case crash ratings for both new and used cars show that many small cars out-perform bigger cars on safety and are more fuel efficient as well. Buy for what you usually do, not what you sometimes do If most of your driving is short trips, why pay more for a big car? If you only go on holiday or need to tow a trailer a few times a year consider buying a small car for everyday driving, and hiring or borrowing a bigger car when you need it. By giving up the weight and power youre not using anyway, you could save a lot on fuel bills and be kinder to the environment. Not all emissions are equal Cars create two types of emission carbon dioxide (CO2) and pollutants. CO2 is widely believed to be the main greenhouse gas contributing to global climate change. Pollutants such as nitrous oxides, carbon monoxide and particulates contribute to smog and can create health problems for people. CO2 output relates directly to how much fuel you use, so the more fuel efficient your car, the less CO2 youll produce. The amount of pollutants you emit comes down to how cleanly you burn the fuel. They are measured in different ways you can look up ratings for both on this site. Safety features could save your life Your chances of being hurt in a crash or having one in the first place are dramatically reduced if your car has certain features. Research suggests that ESC (electronic stability control) can reduce your chances of crashing by around 30%. Airbags have reduced injuries and saved the lives of thousands of people in serious crashes. (Of course, a safe and in-control driver is still the most important safety feature!) Obtain, then maintain How you treat your car has a major impact. Only with regular servicing and maintenance will your car be as clean running and fuel efficient as it should be. When youre buying a used car, ask for its service history and get a vehicle inspection from a suitably qualified person. Spend now to save later In general, improved technology means newer cars are more fuel efficient than equivalent older cars. If youre tossing up over a price difference of a few thousand dollars, think about how long youll own the car and the extra money youll spend on fuel if you go for an older, less efficient model. It may be cheaper to spend more up front.