2009's Most Fuel-Efficient Vehicles

Gas prices are still well above $2 a gallon across most of the country and, with the economy hurting, fuel efficiency should be a determining factor for any car buyer. It's only natural that consumers would first consider Japanese cars, with their proven track record for delivering high gas mileage.

"Honda, over the breadth of its line and history, has generally led in fuel mileage," says Karl Brauer, editor-in-chief of Edmunds.com. "Toyota has done well, too."

Actually, it's the German manufacturers that are leading the most market segments in terms of fuel efficiency on 2009 models. Across the new model year, six from Daimler AG and Volkswagen AG (other-otc: VLKAF.PK - news - people ) rank among the most fuel-efficient, beating every new model in five classes and tying in one. Japanese models placed at the top of only one category (but tied in two); one South Korean model was the best in its category, and one category and one tie went to American cars.

Behind The Numbers
To find the most fuel-efficient cars of 2009, we looked at each model's combined city and highway gas mileage provided by Environmental Protection Agency site fueleconomy.gov (or Edmunds.com, if the EPA didn't yet have the information), and checked those findings against the manufacturers' gas-mileage claims. The figures were compared in 10 market segments, with the best in each making our list. In the case of a tie, both vehicles are included.

Of no surprise is the presence of the popular Toyota Prius, which gets an EPA combined fuel economy of 46 mpg. The only vehicle that approaches its gas mileage is the Honda Civic hybrid, which delivers a highly respectable 42 mpg.

Where the German automakers top vehicle segments, most interestingly, is with diesel models: The Volkswagen Jetta TDI tops the hatchback class, while the Mercedes-Benz E320 Bluetec is the most fuel-efficient luxury sedan.

"Diesel models feature simpler engine design, less energy lost to heat and a more efficient way to utilize fuel," says Brauer. "They're poised for more success today because of the price of fuel, because of clean diesel technology, and because diesel models are great to drive. There has been a huge stigma on diesel from the past, but the truth is that if you put anyone into a modern diesel vehicle, they'll have to redefine their perspective of what diesels are like."

Hyundai Elantra (Family Sedan)

Base MSRP: $15,120

Gas Mileage: 28 (25 city, 33 highway)

Horsepower: 138

For more Forbes.com autos coverage, see:

Best Hybrids For The Buck

Ten Diesel Cars We'll Soon Be Driving

Most Fuel-Efficient American Cars

Tie: Audi A4 (Upscale Sedan)

Base MSRP: $30,700

Gas Mileage: 25 mpg

Horsepower: 211

For more Forbes.com autos coverage, see:

Best Hybrids For The Buck

Ten Diesel Cars We'll Soon Be Driving

Most Fuel-Efficient American Cars