Thirty years ago, Caterham Cars struck a unique and historic deal with Lotus.

Having been involved in the sale and development of Colin Chapman's celebrated Seven since 1959 (including its involvement in the 60s cult television series, The Prisoner), the Surrey based firm now became its saviour.

Against a backdrop of power cuts, rampant inflation, the advent of VAT and the three-day week, Lotus was looking to end production of the Seven as it began to turn its attentions elsewhere.

Caterham promptly stepped in.

In June 1973, the company agreed to take on the manufacturing rights of the Seven, and in doing so, secured its long-term future. Chapman said at the time: "As one of the original Lotus centres, Caterham have an exemplary record for servicing and selling the Lotus Seven, so I am pleased to be able to hand over the rights to them."

The move was an historic one, as Graham Nearn, Chairman and the driving force behind Caterham since the fifties, said a few years later: "Caterham became custodians of the legend."

Three decades, and ten thousand sales later, Caterham has spawned an incredible forty different interpretations or limited editions of the Seven including the Cosworth BDR-powered 1600 from 1983, the 250bhp JPE from 1992 and the Superlight R in 1997.

By preserving the external dimensions and shape of Chapman's original design, and religiously applying his doctrine of engineering out unnecessary weight, the modern day Seven remains a breathe of fresh air and world beater.

The current flagship Superlight R500, which was first seen in 1999, is still the fastest production car on the planet with an astonishing 0 to 60mph time of 3.4 seconds and the ability to complete 0-100-0mph in just 11.44 seconds.

The fastest growing model is the Roadsport SV - accounting for thirty percent of all sales.

As the latest new Seven, the SV was launched in 2001 with an extra few inches in the leg and the side to improve comfort for the 21st Century driver. This was a widely applauded move given the original Seven was built around Chapman's 5' 6" frame.

Although there are ten official versions in the current Seven family, no one Caterham is the same. "Every customer is different so why should they each have the same car?", explains Simon Nearn, Graham's son and now managing director. "That is the spirit of the Seven - individuality."

Graham Hill, Derek Bell, Emerson Fittipaldi and Francois Cevert all cut their teeth behind the wheel of a Seven, so it's no surprise to hear that motorsport continues to play a central role in the continued success of Caterham.

In Japan, US and Europe, over 600 racers compete annually in the 12 one make championships dotted across six countries to make the Seven the most raced car in the world.

"Bearing in mind that the Seven was designed by Chapman as he sought a fresh injection of cash, its longevity and continued appeal is testimony to his genius," concludes Nearn.