What are the most fuel-efficient cars on the market? We researched the highest mileage vehicles available for sale today, using the EPA's Fuel Economy numbers as our guide. Of course, our list leaves off certain small electric car manufacturers because you can't buy those in all parts of the country. Our list represents vehicles that you can buy pretty much anywhere in America. Remember that your fuel mileage will vary depending on your driving style, but all of the vehicles on this list are efficient for their respective segment. We've used the EPA's specific market segments for our classifications, so you can find the highest MPG car for your particular needs.

Overall Most Efficient - Toyota Prius

MSRP: $22,000 - $27,270

Fuel Economy: 48 mpg Hwy/51 mpg City

The Prius is available in four trim levels - Prius II, Prius III, Prius IV and Prius V - with a base Prius I trim scheduled to arrive later in the model year. All trim levels employ Toyota's Hybrid Synergy Drive, a hybrid powertrain technology that unites a 1.8-liter Atkinson-cycle four-cylinder gasoline engine with a powerful electric drive motor to generate 134 combined horsepower, mated to a continuously variable transmission. Every Prius is equipped with a high level of standard equipment: Prius II trims feature 15-inch alloy wheels, power heated mirrors, remote keyless entry with driver door Smart Key passive entry, automatic air conditioning, cruise control, MP3 capability and driver's seat height adjustment; Prius III trims add Bluetooth wireless connectivity, satellite radio and upgraded audio with a 6-disc CD changer; Prius IV trims are further outfitted with heated front seats and leather upholstery, while the Prius V boasts 17-inch alloy wheels and auto-leveling LED low-beam headlights.

Two-Seaters - smart fortwo

MSRP: $11,990 - $20,990

Fuel Economy: 41 mpg Hwy/33 mpg City

The smart fortwo with its small stature provides excellent maneuverability in the city. On the road, its exceptional fuel economy makes it a great commuter vehicle.

The smart fortwo is available in either pure, passion, or BRABUS trims. The pure is solely available in coupe form, while the passion and BRABUS are offered as a coupe or cabriolet. Power comes from a 1.0-liter three-cylinder gasoline engine mated to a five-speed automated manual transmission. Standard safety features include electronic stability program, anti-lock brakes, four-airbags, and tridion safety cell.

For 2009 the smart fortwo receives a new performance oriented BRABUS trim.

Two-Seaters - Mazda MX-5

MSRP: $22,810 - $28,250

Fuel Economy: 28 mpg Hwy/22 mpg City

The MX-5 Miata roadster comes in two basic configurations: a soft-top or a power retractable hardtop. Three transmissions are offered, a five-speed manual, a six-speed manual and a six-speed automatic with steering wheel mounted paddle shifters. The only engine available, a 2.0-liter, inline four-cylinder, comes in two power levels, one rated at 167 horsepower with either manual transmission, or 158 horsepower with the automatic. Standard safety equipment across the line comprises dual front airbags with passenger deactivation switch, side impact airbags, tire pressure monitoring and anti-lock brakes with electronic brake-force distribution; electronic stability and traction control is optional on the Grand Touring trim.

Minicompacts - MINI Cooper

MSRP: $18,550 - $23,900

Fuel Economy: 37 mpg Hwy/28 mpg City

The MINI Cooper provides the driving enthusiast with a combination of fun-to-drive performance, engineering and unconventional attitude.

The two-door hatchback Cooper features a 118-hp 1.6-liter inline four-cylinder engine mated to a six-speed manual transmission or optional six-speed automatic. Standard safety equipment includes six airbags, ABS, traction control and stability control. A wide variety of interior trim materials and colors are available. Features such as Xenon headlights, sport suspension, Dynamic Traction Control, power sunroof, navigation system, parking sensors, Bluetooth wireless connectivity and satellite radio are optional.

Subcompacts - Toyota Yaris

MSRP: 12,205 - $15,125

Fuel Economy: 36 mpg Hwy, 29 mpg City

The front-wheel drive Yaris is available as a hatchback (three-door or five-door) or a four-door sedan; all are offered in a Base trim. The Yaris is powered by a 106 horsepower 1.5-liter four-cylinder engine, which is mated to a five-speed manual transmission; a four-speed automatic is optional. The hatchback and sedan were designed separately and have subtle interior and exterior differences but have similar standard content. The base trim comes standard with P175/65R14 tires on steel wheels, cloth bucket seats, and manual tilting steering wheel, anti-lock brakes, and six-airbags.

Compacts - Honda Civic Hybrid

MSRP: $23,650 - $23,650

Fuel Economy: 45 mpg Hwy, 40 mpg City

The Civic Hybrid is only available in a sedan model. It is powered by a 1.3-liter four-cylinder gas engine and a light-weight, brushless electric motor that is sandwiched between the engine and the CVT transmission. Combined, the gas engine and electric motor produce 110 horsepower and close to 45 mpg on the highway. Standard safety features include anti-lock brakes, six airbags, tire pressure monitoring system and active front head restraints.

Compacts - Volkswagen Jetta TDI

MSRP: $22,660

Fuel Economy: 41 mpg Hwy/30 mpg City

The Jetta is powered by three different engines, a 2.5-liter five-cylinder engine generating 170 horsepower, a 140-hp 2.0L TDI clean-diesel engine for those looking for maximum fuel economy, or a 200-hp 2.0-liter turbo in the Wolfsburg Edition. Buyers that go with the 2.5-liter engine can choose between either a five-speed manual transmission or six-speed Tiptronic automatic; while TDI and 2.0T buyers select from either a six-speed manual transmission, or a six-speed DSG auto with Tiptronic. All Jetta's come standard with many safety features including six air bags, anti-lock brakes, electronic stability program, traction control and tire pressure monitoring.

Midsize - Toyota Prius

MSRP: $22,000 - $27,270

Fuel Economy: 48 mpg Hwy/51 mpg City

The Prius is available in four trim levels - Prius II, Prius III, Prius IV and Prius V - with a base Prius I trim scheduled to arrive later in the model year. All trim levels employ Toyota's Hybrid Synergy Drive, a hybrid powertrain technology that unites a 1.8-liter Atkinson-cycle four-cylinder gasoline engine with a powerful electric drive motor to generate 134 combined horsepower, mated to a continuously variable transmission. Every Prius is equipped with a high level of standard equipment: Prius II trims feature 15-inch alloy wheels, power heated mirrors, remote keyless entry with driver door Smart Key passive entry, automatic air conditioning, cruise control, MP3 capability and driver's seat height adjustment; Prius III trims add Bluetooth wireless connectivity, satellite radio and upgraded audio with a 6-disc CD changer; Prius IV trims are further outfitted with heated front seats and leather upholstery, while the Prius V boasts 17-inch alloy wheels and auto-leveling LED low-beam headlights.

Midsize - Nissan Versa

MSRP: $9,990 - $16,330

Fuel Economy: 31 mpg Hwy, 26 mpg City

In keeping with its positioning as Nissan's entry-level car, the Versa lineup is pretty straightforward. It is available as a hatchback or sedan in two trim levels, S and SL. All models are powered by the same 122-hp, 1.8-liter, four-cylinder engine driving the front wheels. Both S trims as well as SL hatches come standard with a six-speed manual transmission. A four-speed automatic transmission is optional on the S trims and standard on the SL sedan, while an advanced Xtronic CVT (Continuously Variable Transmission) is optional on SL hatches. Safety comes from six standard airbags, while anti-lock brakes with electronic brake-force distribution are optional.

Large - Hyundai Sonata

MSRP: $18,700 - $26,550

Fuel Economy: 32 mpg Hwy, 21 mpg City

The Hyundai Sonata is a four-door, five-passenger sedan that has an established reputation for being well built and excellent value for money. It holds its own when compared to other mid-sized cars in this competitive class.

Motivation comes from a 175-hp 2.4-liter four-cylinder engine, with the choice of a five-speed manual or a Shiftronic five-speed automatic transmission. A more powerful 249-hp 3.3-liter V6 mated to a Shiftronic five-speed automatic transmission is also available. Safety features on all Sonatas include the mandatory dual-stage front-seat airbags; front-seat side-impact airbags for torso protection; and full-coverage side curtain airbags, anti-lock brakes with electronic brake assist, and electronic stability control with traction control.

Large - Honda Accord

MSRP: $20,905 - $28,955

Fuel Economy: 31 mpg Hwy, 22 mpg City

The Accord comes either as a two-door coupe or four-door sedan with a 2.4-liter four-cylinder or 3.5-liter V6 engine. The four-cylinder engines are available in five-speed manual or automatic transmission for both styles of the Accord, while the V6 sedan is only available in five-speed automatic. The V6 coupe is available with a six-speed manual or five-speed automatic. Cloth upholstery is standard on all but the EX-L models which feature leather seats and a leather-covered steering wheel. Safety is enhanced on all Accords with six standard airbags, including side-impact air bags for front seats and side curtain air bags. Four-wheel disc, anti-lock brakes, Vehicle Stability Assist with traction control, Brake Assist and active front head restraints also come standard.

Small Station Wagons - Volkswagen Jetta TDI Sportwagen

MSRP: $23,870

Fuel Economy: 41 mpg Hwy/30 mpg City

The Volkswagen Jetta is the best deal in town if you like the idea of a solid sedan or wagon with European flair.

The Jetta line-up has been bolstered with the addition of the new for 2009 SportWagen. There will be three different engines to choose from this year, a 2.5-liter five-cylinder engine generating 170 horsepower, a 200-hp 2.0L turbo borrowed from the GTI, and a new 2.0L TDI clean diesel engine for those looking for maximum fuel economy. All Jettas come standard with many safety features including front side-impact air bags, curtain/head air bags, anti-lock brakes, electronic stability program and traction control.

Midsize Station Wagons - Kia Rondo

MSRP: $17,495 - $22,295

Fuel Economy: 27 mpg Hwy/20 mpg City

The Rondo can be equipped with a third row of seats, allowing it to carry up to seven passengers. The second and third-row seats can also be folded nearly flat which provides more cargo room. Unlike full-size minivans, the Rondos' rear doors open outward in the conventional manner, instead of sliding. Its 2.4-liter four-cylinder engine produces 162 horsepower and is mated to a four-speed automatic transmission. A more powerful 185-hp 2.7-liter V6 engine and five-speed automatic transmission are also available. Safety features include side-impact and side curtain airbags, four-wheel-disc anti-lock brakes and an electronic stability system.

Midsize Station Wagons - Saab 9-5 Sportcombi

MSRP: $39,650

Fuel Economy: 27 mpg Hwy/17 mpg City

The 2009 Saab 9-5 provides performance, luxury and value in a stylish and comfortable European design.

The front-wheel drive 9-5 is available as a four-door sedan or wagon (SportCombi). Seating five passengers and standard with 17-inch wheels the 9-5 is now available in one trim: the Griffin. The 9-5 is powered by a 260-hp turbocharged 2.3-liter four-cylinder engine, available with a five-speed automatic with manual gear selection or an optional five-speed manual transmission. Safety features include Xenon headlamps, all-disc anti-lock brakes, traction control, an electronic stability program, front side-impact airbags, Saabs' anti-whiplash Active Head Restraints, and rear park assist.