In 1989 he was described as the English equivalent to Oscar de la Renta, and "the master of the English thoroughbred look". He now works as a painter. In 1962 he began working as a trainee designer for Alexon.
As well as Alexon and Salvador, he worked for Nettie Vogues, Clifton Slimline, and Biba.
In 1970 he launched his own label although it was short-lived. He then went on to spend three years working for the London branch of Christian Dior South America under the direction of Jorn Langberg, before re-establishing his label in 1978.
In 1982, Edelstein decided to focus exclusively on haute couture, and also designed for the theatre and ballet. Edelstein"s workroom was based at Stanhope Mews West, London.
His most famous design is probably the ink-blue velvet gown he created in 1985 for Diana, Princess of Wales, to wear to the White House, where she danced with John Travolta.
This dress, on both occasions it sold at auction, set world record prices for a dress worn by Diana (£137,000 ($222,500) in 1996, and £240,000 ($362,424) in 2013). In the late 1980s, his prices were often around the £2,400 to £2,500 mark for an evening dress, with his clients typically buying three or four outfits each season (an evening gown, a suit, and one or two dinner dresses). Edelstein closed his fashion house in 1993, explaining that there was no longer a market for luxurious custom-made clothing.
Since then, he has established himself as an artist, exhibiting his work throughout Europe and the United States.