Design: Dinah lights the way at the V&A

How do you take three centuries of British decorative arts out of their dusty cabinets and bring them alive? Easy, says Dinah Casson. Nonie Niesewand learns how.

The architect Dinah Casson stands in the awesomely gilded rococo room at the V&A, transplanted from elsewhere, and considers the task before her - it is exciting but challenging; no less a thing than trying to revive interest in the British Gallery of decorative arts 1500-1900 (Henry VII to William Morris).

"I want people to gawp, and swoon and smile at things." says Casson. "Gawp at the scale of the Melville Bed. Or at the Margaret Laston bodice, so exquisitely made and tiny that it's breathtaking. And I want them to swoon at the beauty of 17th-Century formal gardens all executed in tiny stitches on a 7 metre long embroidery called the Stoke Edith hanging."

It is, as its curator, Christopher Wilk, calls it "one of the most remarkable collections of design and art in the world." And yet, with the exception of the three period rooms, it is housed in galleries, 15 of them, so overstuffed and dimly lit that average time that visitors stay is no more than 11 minutes.

In June, the galleries will close for air conditioning to be installed and (lottery funds permitting) that will the beginning of a transformation which Casson, her partner Roger Mann and decorator David Mlinaric will bring about. The whole project is expected to cost just under pounds 34m.

Getting Dinah Casson to design the displays was enlightened. She has a playful approach to interiors - the offices she designed at Turner Cable Network have a fishtank for a reception desk and cacti growing in the boardroom like coat hooks, while the Institute of Practising Advertisers, in a Grade I listed Knightsbridge building has a shiny metallic entrance wall made of crushed aluminium cans.

In the scale model she has made of the V&A British Gallery, walls are coloured in intense indigo and aquamarine. A miniature she's made of the gigantic State Bed from Melville House, which is 5m tall from its clawed foot to the top of its ivory silk canopy, stands against a crimson wall. If a tapestry dating back to Charles II needs a shocking pink surround, it will get one.

Dinah who likes contrasts, sees nothing wrong in placing a Queen Anne chair against a bare concrete wall, and she has every intention of using repro chairs that people can sit down in to admire the original in front of them.

She isn't a bit intimidated by working with more than 3,000 priceless objects. Editing the collection so that people won't be bored or overwhelmed, she wants to turn it into four storylines that people can follow.

The first narrative is called "Cultural Authority", which is really a political story about taste makers, from the king and courtiers to the Grand Tour and neoclassicism, with Gothic influences continuously making appearances, and ending with William Morris and his merrie band of craftsmen.

Then there's "Development of Style", which shows foreign influences as well, so you can see where Chippendale got his Chinese scrollwork and Brettingham his rococo flourishes.

"Fashionable Living" explains just why people through the ages bankrupt themselves to buy a silver rosebowl or petit fours dish. As Casson says, "Nothing changes. We still look for designer labels - whether it's a Gucci watch or an Alessi kettle"

The fourth theme shows how things work. She plans to lift the hemline on sofas to show the stuffing, and to place mirrors on the floors under tables and cabinets, and turn chairs around to give us another look at it. Not just undersights, but insights.