Over the past years, the international art trade has completely been transformed. Contemporary art has gained ground, and the contemporary auction turnover of Christie's and Sotheby's, the two major auction houses, has increased threefold over the last two years, which is indicative of a change to the prices in the first place. It was for the first time that Christie's and Sotheby's, the two leading auction houses, made an appearance at TEFAF, the most noted worldwide art fair, in Maastricht, in the Netherlands, although they did so with names different from their own and contrary to opposition from art dealers. The works of art by outstanding 20th-century modern artists sell at astronomical sums. Accordingly, nearly ten works of art have been entered into the list of works sold at over one hundred million US dollars.