Volkswagen Group will concentrate future models on just four platforms or architectures.

According to the Automotive News they are for compact rear-engined city cars, code-named MHB, small to midsized transverse-engined family cars (MQB), mid-engined sports cars, and larger longitudinal-engined cars (MLB).

This strategy is designed to help Volkswagen meets its stated aim of producing 10m cars a year by 2018, up from six million at present, whilst also reducing costs by 25-40%.

The MHB will form the basis of the new small rear-engined Up! City cars. According to the UK's Autocar, it will also form the basis of the Seat city car, known as the Ros. A Skoda model could follow. This architecture is expected to provide a significant proportion of sales growth, as most of the growth in the global car market in the next 10-15 years is expected to be in small and low-cost cars, particularly for emerging markets.

The MQB platform will be the largest. According to Autocar it will form the basis of a variety of front, transverse-engined, front-wheel drive cars, ranging from the VW Polo up to the Passat. The architecture will be so flexible that the different brands will be able to vary wheelbase and track width almost infinitely. Common amongst all models will be components, manufacturing processes, front axle, pedal box and the positioning of the engine. The first new model on this architecture could be the Audi A1 in 2010.

The mid-engined sports car platform is currently under development. Autocar reports that the Porsche Boxster and Cayman will use this architecture, but it could also be used by Lamborghini and Bugatti.

MLB is the largest platform and already underpins Audi A4 and A5. It will support the next Audi A6 as well as the VW Phaeton and next Bentley Continental GT.