'It was a case of appreciating the medium but not the design,' she says. Mason then specialised in 'couture decals', which she describes as a contemporary approach to the decor that used to be applied in Europe's grand old houses.

Inspired by the intricate detailing and extravagant quality of materials used in these residences, Mason put months of painstaking work into each of her decal designs.

Decals, from the French decalquer (to trace or transfer), are not new. They were first applied to English pottery in the late 18th century. The word is short for 'decalcomania', a term coined to encompass the ensuing craze for these decorated ceramics. Industrial decals soon followed and modern versions have since decorated surfaces from model planes to cars and shopfronts.

During the 1950s, large decals of comic-book characters became popular in children's rooms across America. Until a few years ago, wall decal ranges were limited to Disney characters and graphics for kindergartens. Low in quality, they looked like obvious stickers, quick to fray and unlikely to last more than a few months.

These days matt-effect decals can seem painted on if they are properly applied to any dry, flat surface. They can also be used beyond walls and windows to embellish floors and ceilings, tiles and even furniture. Typically lasting for a minimum of three years, decals are usually unaffected by condensation but are easy to wipe clean and, crucially, can be peeled away without damaging any paintwork.

Often designed in a set, decals also offer creativity to the non-artistic. Mason describes their design as 'rather fiddly and handmade', but a perfect result is virtually guaranteed because decals are manufactured and 'computer-etched with lace-like intricacy and accuracy'.

Even children's decals have been given the high-design treatment and parents no longer need to be restricted to Winnie-the-Pooh motifs. Florida decal designers Wee Gallery was launched by a couple who learned that newborns can see only about 30cm away and are most taken with faces and black-and-white geometrical designs. Its animal decals are designed to appeal to very young babies and toddlers.

California-based Blik began operating in 2002 and was among the first companies to introduce a range of designer wall decals. Initially purveyors of 'wall poetry' - large-scale texts in eye-catching fonts and colours - Blik added bright geometric designs to its repertoire as well as witty visual commentaries on living in flats, including a stylised set of floating bookshelves and a 1.2-metre caged bird backed by a circle of blue sky.

Other notable design-led companies include France's Les Invasions Ephemeres, which specialises in intricate feminine designs inspired by Marie Antoinette, and Belgium's Apple Pie Design with a range of life-sized silhouettes.

Decals have also caught the imagination of small-flat dwellers in South Korea and Japan, where Mason launched her first products.

Decals are perfect for Tokyo interiors, she says. 'They don't take up any room. They take no time at all to put up but the final result is really spectacular.'

However, decals have yet to take off in Hong Kong. Lane Crawford features life-sized chandelier decals in its displays and colourful children's wall stickers are available at other local outlets, but you are still more likely to see a painstakingly painted mural than a decal that merely looks like one. Despite the popularity of decals in the US, the local residential interiors market has yet to be tested.

The in-your-face mural effect is not to everyone's taste, but the decal technique can also be used in more subtle room treatments. Decals of frosted miniature flowers can be applied to windows for a modern take on net curtains and a glossy white feather motif on a matt white wall can catch the light and add 'luxurious texture to a room', Mason says.

She is also working on 'blackboard vinyl', which can be drawn upon, giving flat tenants another form of expression within the decoration terms of their lease. After a therapeutic graffiti session on your living room wall, you can just peel it all away.