There's a quiet revolution going on in the mid-size family car sector. Otherwise known as the default company car market by the reps pounding the motorways - quality, refinement and style have all been ramped up a notch in recent years.

The reason is a simple one: the volume car sellers are having to compete with the premium big boys - Audi, BMW and Honda.

Regular cars are no longer ticking all the right boxes for increasingly choosy drivers, which is why these particular vehicles have been getting bigger and more upmarket in the looks and equipment departments.

Renault's answer to this change in buyer behaviour is this latest generation Laguna. And right from the start it's plain to see that the car is aimed at people seeking out premium metal.

Renault's designers have opted for a fuss-free approach for the exterior, making it all about the details - the rear lights located high up on the car's tailgate, the single sliver of chrome running the length of the front bumper and the smooth, Alfa 159-like crease-free flanks.

It still looks like it's descended from the Laguna family tree, but this variant has ditched the £100 high street suit for something a little more expensive.

The same is true of the Laguna's cabin, for it too has been to finishing school.

The plastics have an Audi look and feel to them, while the fascia isn't cluttered with an uncomfortable mix of switches and dials in a misguided bid to impress.

In fact, the central portion contains an intuitive cluster of ventilation controls, while down by the gear-lever there's a nifty rotary controller surrounded by buttons for the information and entertainment system and sat-nav, if fitted.

Secondary audio controls are on the steering column and the main dials are clear, bright and would not look out of place in something costing a lot more.

The detailed improvements are welcome, although the most obvious changes concern the car as a whole.

On the performance front, the old Laguna was never marketed as a sharp driving tool. In fact, Renault was more than happy to see the car viewed as a relaxed mode of transport.

This remains true with the new car, but where precision was absent from the old car's controls, the opposite is true today.

Granted it's no BMW-beater - but there are considerable improvements in performance and handling.

It reacts to commands more quickly and is responsive when you want to drive briskly, making it a sharper car in every respect.

On the road the car is something of a surprise. As well as responsiveness, there is also a level of general refinement that is streets ahead of the Laguna's direct rivals.

Playing a big part is the Laguna's engine range. Some will be familiar to Renault drivers, but there are also some new units with a wide choice in terms of power and economy.

For fleet managers the diesel option has become the automatic choice. And Renault's two litre 150 horsepower dCi unit is a great all-rounder - powerful, quiet and economical.

And with an optional auto gearbox, it should also appeal to private buyers keen to combine economy and convenience.

There is another diesel in the shape of a 1.5-litre, 110 horsepower unit, which is something of a surprise.

Connected to the Laguna's default six-speed manual gearbox, this engine is surprisingly lively, never feels underpowered and, thanks to its modest capacity, is very frugal.

The Laguna's performance might be a pleasant surprise, but it's also good to know that some things don't change.

The focus on safety is as determined as ever - airbags are everywhere and the car's structure is very strong.

And there's a generous level of standard kit across all the trim levels, plus no shortage of choice when it comes to optional extras.

Renault isn't promoting the Laguna as a sports car but more of an all-rounder, which makes sense given the engines offered, the cabin ambience and the overall refinement.

Essentially, what Renault is doing with the Laguna is playing the sophistication card and it works well.

And when it comes to driver confidence in the quality of the car, Renault has provided a three-year 100,000-mile warranty, which should provide peace of mind.

Model: Renault Laguna Dynamique 2.0 dCi 150 Engine: 2-litre diesel Performance: 0-62 in 9.5 seconds, top speed 130mph Economy: 47.1mpg combined Co2: 158g/km Price: From £18,400 Web: www.renault.co.uk