In 1982, he and Mara Cremniter opened the Downtown gallery on rue de Seine in Paris, specializing in modern furniture, in particular 20th century architectural furniture, especially that of Oscar Niemeyer, Jean Prouvé and Charlotte Perriand. According to L’Express, in the 1970s he acquired “entire lots of these [two] designers for almost nothing”, especially at Emmaüs sales, but also “at the Cité Universitaire [and] in the administrations of the Congo or Mauritania”. François Laffanour says about a chair by Jean Prouvé bought in 1975 for 20 francs: “I bought things that others didn’t want, but which I perceived the interest, functional or aesthetic, even if I had no notion of their rarity.

In 2006 he acquired the archives of the Steph Simon gallery, which between 1956 and 1974 published and sold the creations of Jean Prouvé and Charlotte Perriand, Serge Mouille and Georges Jouve.

Since 2007, François Laffanour is a “pillar of all the fairs” of art and design such as the Biennale des antiquaires, TEFAF (Maastricht), Design Miami & Design Miami/Basel, PAD Paris and PAD London, as well as The Salon (NYC)…