Having persisted longest with single-category auctions in many traditional collecting areas, they will now follow Sotheby's and Christie's in combining several disciplines in one auction. The hope is to attract new and crossover buyers.

Bonhams will be holding four sales in the summer and autumn, two devoted to British material and two for European works. The first titled Britain: Defining the Interior, takes place in New Bond Street on June 3 and will offer furniture, sculpture, works of art, ceramics, British and Colonial silver and portrait miniatures.

European furniture, works of art, sculpture, silver and gold boxes will be covered in the sales titled Europe: Defining Style, the first on July 9. European ceramics will continue to be offered alone.

Saleroom followers will already be familiar with this approach from auctions like Christie's 'Centuries of Style' and Sotheby's 'Arts of Europe' sales.

Specialist Sales

However, those who still want the traditional single-discipline sales will not be abandoned. Bonhams' specialists will continue to provide fields such as ceramics and silver with dedicated sales in their Knightsbridge rooms.

Bonhams' silver specialist Michael Moorcroft, one of those involved in the new format auctions, said the new format reflects the evolution of the market.

"The profile of the collector is definitely changing. The old collector that kept certain categories going is not so much in evidence. There is more buying for the look," he said.

But he added: "We don't want specialist collectors disappearing. There will still be British ceramics and glass sales at Knightsbridge directed towards the specialist collectors' fields and we continue our series of regular silver sales and post-War silver at Knightsbridge. We are embracing the mixed-discipline sale without abandoning the single-discipline sale."