He transformed L’Oréal from an SME, founded in 1909 by Eugène Schueller, into the world's leading cosmetics and beauty products company.

At the time, he had the ambition of pursuing a career in law, but the fall of France to the Nazis in 1940 forced him to give up working for his agrégation (teaching certificate), and to continue on this path.

For a time a lawyer at the Paris Court of Appeal, from 1941 to 1942,[1] he met Eugène Schueller through his friend André Bettencourt.. After a brief interview he was hired at "half of today’s French statutory minimum wage"[2] as assistant to the secretary of the sales director at the Monsavon factory in Clichy (92), and rapidly rose through the company's ranks to become factory manager then chief executive officer of the Monsavon company in 1945.

Lastly, he was a director of the Banque Nationale de Paris (BNP) from 1973 to 1982, of les Éditions Masson from 1975 to 1984, Air Liquide from 1986 to 1992 and TV Channels stations Canal+ from 1985 to 1994 and TF1, from 1987 to 1994.

[citation needed] François Dalle died on 9 August 2005 in Geneva in Switzerland, leaving six children: Jean-Francois, Guyonne, Pierre-Jérôme, Frédéric, Jean-Baptiste and Violaine.

In keeping with his wishes, he was cremated and a mass was celebrated in his memory in the Les Invalides Church in Paris attended by, among others, Valéry Giscard d'Estaing, Lindsay Owen-Jones and Liliane Bettencourt.

[citation needed] A demanding businessman, but always caring towards his employees, François Dalle succeeded in transforming a French SME into one of the key players in cosmetics, making it the world leader in beauty, with brands as emblematic as L’Oréal Paris, Garnier, Mixa, Lancôme, Diesel, Biotherm, Yves-Saint-Laurent and Armani.

Businessman Jean Frydman accused François Dalle of having forced him to resign from the management committee of Paravision, L'Oréal's audiovisual subsidiary in which he held 25% of the shares.

The reason for his ousting was allegedly to satisfy the demands of the Arab League, which was boycotting any company with direct or indirect links with Israel.