Cast your mind back to motoring, say, fifteen years ago. Those with a small family had the choice of packing their offspring and luggage into something tiny, opting for a boring hatchback or bending the budget by splashing out on a lumbering family saloon. From Vauxhall's perspective, the Nova/Astra/Cavalier conveyor belt worked only because there was little alternative. Fortunately, more recent niche marketing techniques have seen this broad brush approach consigned to history and Vauxhall in particular have moved astonishingly swiftly for such a large company. Take the Meriva, a small car that lives big, featured here with a clever common rail diesel engine. This CDTi model offers an insight into how far we've come in fifteen years.

The engine itself is an astounding achievement. With 100bhp on tap, it's more than enough to give this supermini-MPV a respectable turn of pace but more importantly, it promises super-low fuel consumption and CO2 emissions. The engine complies with stringent Euro4 emissions regulations which means a three per cent discount in benefit-in-kind taxation for company users. Mind you, it's unlikely that too many fleet managers will consider the Meriva. This is a family friendly car that makes a lot of financial sense to the fleet manager at the head of any household.

Expect to average over 51mpg yet the Meriva 1.7CDTi will accelerate to 60mph in a reasonable 13 seconds and top out at 109mph. A full 177lb/ft of torque makes the Meriva feel muscular through the gears and the engine is pleasantly refined. This is because the high pressure injection system can exercise greater control over the fuel delivery which means that the combustion process is smoother, fuel economy is improved and emissions are reduced. An electronic on-board diagnosis computer permanently monitors the engine's emissions performance, tuning the combustion process to offer optimum cleanliness. You'll feel the benefits of the CDTi engine right from the moment you turn the key. Whereas old Vauxhall direct injection engines felt potent but a little crude, this diesel feels a good deal more urbane, but has the requisite acceleration in the midrange that's the mark of a decent diesel.

To say that a great deal was expected of the Vauxhall Meriva has to be something of an understatement. It's big brother, the Zafira, rewrote the rulebook for mini-MPVs when it was launched back in 1999, offering seven seats when everyone else was packing five. Ford and Volkswagen were forced to head back to the drawing board with their designs, buying Vauxhall a few years breathing space. The Meriva has been achieving similar success in the supermini-MPV sector.

"177lb/ft of torque makes the Meriva feel about as muscular as a V6 Mercedes E240 through the gears "

To date, this market segment hasn't been the most dynamic, yet it shows great potential for growth. Oddball Japanese supermini-MPVs like the Daihatsu Move failed to capture the British public's imagination, and Vauxhall's take on the Suzuki Wagon-R, the Agila, also enjoyed only modest success. Cars like the Ford Fusion and Honda Jazz offer certain MPV-style utility features but still have one foot rooted in the comfortable familiarity of the mainstream supermini market. The Meriva is cut from very different cloth, as are key rivals like the Renault Modus, the Peugeot 1007 and the Fiat Idea.

It's based on a Corsa platform, making it a good deal smaller than a Zafira, which rides on Astra mechanicals. At 4,042mm in total length, its still a tad shorter than an Astra, but with its wheel at each corner stance and it's high roofline, the General Motors designers responsible for the Meriva have been able to create an interior that's supremely spacious. Trim levels run through Expression, Life, Club and Design to the mighty VXR - yes, Vauxhall do offer a high-performance supermini MPV. The current Meriva models can be picked out by the Vauxhall trademark V-shaped grille set in a reprofiled front bumper along with dark lens rear light clusters and a thick chrome strip across the tailgate. They have also benefited from some interior trim upgrades.

As with any vehicle that touts itself as some sort of MPV, the Meriva stands or falls on more practical considerations such as interior space, the ingenuity of its seating system, passenger access and overall comfort. It's here that the Meriva comes up trumps. Just as Vauxhall aced the opposition with the Zafira's Flex7 seating system, the Meriva aims to do likewise with its less snappily titled FlexSpace arrangement. With five seats to play with, the Meriva doesn't have as many tricks up its sleeve as the Zafira, but you'll still be able to wow your passengers with a few deft flicks of the wrist.

Most of the time, the Meriva functions as a conventional five seat supermini-MPV, but many of us have tried travelling five up in cars like these and it can feel a bit of a pinch. The Meriva goes some way to alleviating the problem by offering one of the widest rear passenger shoulder width measurements in its class, but the real benefit comes when travelling with four rather than five aboard. The centre seat can fold flat into the footwell, leaving the two remaining seats at liberty to slide independently, not only backwards and forwards, but also on runners from side to side. This makes the Meriva feel extremely spacious indeed. But why stop at four? Vauxhall have equipped the Meriva with the capacity for all of the passenger seats to fold flat, freeing up an enormous 1,300 litres of available space. Even with the rear seats in position, there's a creditable 560 litres available.

With a wheelbase barely two and a half inches shorter than a Vauxhall Zafira, the Meriva demands few compromises on its occupants. The 1.7-litre CDTi engine rounds off a very competent package and although it may not be the most exciting car in its class, it might just be the cleverest. For a snapshot of current state of the art compact family motoring, look no further.