But while VW may be leading the charge toward scalable architectures, it is far from alone. Among those jumping on the bandwagon are Renault-Nissan, Volvo, Jaguar and, most recently, General Motors. Other automakers appear to be headed in the same general direction, as well, if not following the exact same path.

“The thing that everyone is going after now is increased flexibility in all three directions,” says Hau Thai-Tang, former chief engineer for Ford and now its head of purchasing. “So in longitudinal, with wheelbase and in the lateral.

“There’s a lot of benefit with that scale in terms of engineering savings, material-cost savings.”

Ford won’t merge its B- and C-model architectures as some competitors are doing, Thai-Tang says, but he points to its steady reduction in the number of platforms overall from 27 in 2007 to 15 today and on to a planned nine in 2015. By 2017, the automaker expects to average four different models in production at each assembly plant worldwide.

In the case of Renault-Nissan, development of a second flexible platform is well under way, following launch of its Common Module Family architecture for C/D-segment vehicles that is providing the basis for about 13 Renault and Nissan models.

This new platform, dubbed CMF-A, uses some of the same core principles as the CMF-CD but is aimed at smaller vehicles targeted primarily at emerging markets such as India beginning in 2015. A slightly larger CMF-B architecture is on deck as well, which could share key components with the CMF-A.

Jean-Michel Billig, executive vice president-engineering and quality, tells WardsAuto the CMF-A consists of five main modules: the engine compartment, front underbody, rear underbody, cockpit and electrical/electronic architecture.

Each of these major pieces could have up to three versions designed to accommodate different vehicle types and price points, allowing Renault-Nissan to choose from among the building blocks to produce a variety of models, from sedans and hatchbacks to wagons, pickups and multipurpose vehicles.

“You may have one to three different Lego pieces for each big module,” Billig says. “Then you will look at which is the best, the optimum combination, in order to address a given market. If you want to make an SUV, you may not have the same combination as if you want to address a sedan or a pickup or wagon.”

PSA Peugeot Citroen has a similar architecture under development called the Efficient Modular Platform 2, which reportedly will cover half its volume by 2014. It debuted with the new C4 Picasso, but also is to be shared with GM for a new Opel Zafira in 2017, if the tie-up between the two automakers goes forward as planned.

At September’s Frankfurt auto show, Volvo unveiled its Concept Coupe based on its upcoming Scalable Product Architecture that eventually will support all of the brand’s models above the 40-Series in size, beginning with a new XC90 CUV in 2014. Jaguar exhibited the CX-17 CUV concept derived from its aluminum-intensive IQAL platform that will underpin a number of diverse vehicles beginning in 2015.

Executives at Toyota, which has been among the leaders in applying common engineering across vehicle lines, have indicated even more parts-sharing is needed to remain competitive. Its TNGA platform that reaches the market next year with a new Prius ultimately will cover seven vehicle segments, replacing its current MC platform that spans just five, WardsAuto/Automotive Compass data shows.

Volkswagen’s flexible-architecture lineup isn’t limited to the MQB, either. It also has the New Small Family platform (PQ12) that supports its Up line of entry-level vehicles, the MLB that spawns Audis and other models with longitudinal-engine layouts and an upcoming sports-car platform that will be shared by multiple brands, including Porsche.

The list goes on. WardsAuto/AutomotiveCompass data show this year about a third of the top-volume platforms will cross four or more size segments. By 2019, that percentage will go to half, and those will span up to seven market segments.

“Most everybody at one level or another is going after this same belief,” Hoffecker says of scalable architectures.

Renault’s Billig agrees. “We have not started our thinking…yesterday. And, by the way, we are not the only one. Some of our competitors are thinking in the same way.”