In Britain there has always been a proud tradition of family-run firms. Companies such as Wedgwood, Chippendale and Liberty all flourished safe in the knowledge that their line of succession was secure, with the best seat in the boardroom kept warm from one generation to the next. But in an age of hostile takeovers and management buy outs, not to mention the unwillingness of offspring to meekly progress into the family firm, the old certainties have gone. So what is it that drives a younger generation to follow the career paths their parents have already blazed? Inherited talent? Pressure to keep the family name up there in lights? Shared interests? We talk to three design dynasties to find out.

James Dyson, wife Deirdre, daughter Emily and son Jake

There's no family business as such to tie together the Dysons, but they do share a collective creativity. James is famed, of course, as the inventor of the bagless vacuum cleaner, and his wife Deirdre for her carpet and rug designs. Son Jake, 34, has followed a parallel path to his father, setting up his own product-design company, while daughter Emily, 36, has her own bedlinen and childrenswear shop, Couverture. James and Deirdre think that it isn't so much inherited abilities that have encouraged their children to strike out on their own, but an upbringing that instilled in them the value of taking a chance. "I am more afraid of regretting not trying, than not succeeding," says Deirdre."

There's no history of business acumen in my family," admits James. "My parents were good amateur painters and our heritage is of teachers and vicars, not entrepreneurs. My father died when I was young, so I started repairing things around the house and through that became interested in how they were made and functioned."

The designer Jeremy Fry gave James his first break and "turned a long-haired Royal College of Art student into an entrepreneur" by taking on "Sea Truck", Dyson's high-speed maritime vehicle project. After that, Dyson set up on his own and struggled to establish his bagless cyclonic cleaner and to safeguard its patent.

Deirdre's career had a delayed start. "I did a secretarial course and spent six years working before doing what I really wanted to do, and got a place to study at the Byam Shaw School of Art." And it was while at art school that she met James who was also studying there.

Although she has long been an established and exhibited artist, Deirdre didn't want her children to experience the "wasted" years that she had. "We've always encouraged the children to follow their instincts and to be proud, not ashamed of failure."

Jake recently launched Motorlight, an adjustable up-lighter the strength of which can be varied from ambient to spot. "At school I once got in trouble with an art and design teacher who accused me of getting Dad to do my technical drawing homework. Some people find it difficult to accept that you have ability of your own," he says.

He studied product design at Central Saint Martins, worked in interior design and created a range of robotic cabinets for the jewellers Jess James. He spent three years teaching himself engineering and three more working out of a garage before establishing a studio in Clerkenwell. The Motorlight is his first commercial product. "Occasionally I'll ask Dad for business advice, but this is my idea. What my upbringing has done for me is made me prepared for the pitfalls of business. I have experienced the ups and downs first-hand, so I know better than most how to cope."

"There is a slight feeling of dread about Jake's choice of career," admits Deirdre, "a feeling of 'here we go again', but it is his life and he must do with it as he wants."

Having studied fashion design at Nottingham Trent University, Emily went on to work for Paul Smith. "I always swore I wouldn't set up a business on my own, I'd seen how hard it was for Dad," she says, recalling the times when pocket money was scarce and "when doors were kept closed and we knew we had to be quiet. But in spite of that something in me made me do it; at the time it did seem to be the only way forward."

Seven years ago Emily opened her shop Couverture on the King's Road in London. "I used my background in design and interest in hand-worked detailing to create a range of bed linen and pyjamas, but I wanted them to be part of a whole look, so I added vintage furniture and accessories as well as ranges for children. I deliberately avoided using the Dyson name; everything is under the Couverture label because I didn't want to ride on the back of what Dad had achieved."

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