Arnault's entry into the luxury sector was marked by his strategic acquisition in 1984 of the financially-struggling textile and retail conglomerate Boussac Saint-Frères, which included the prestigious fashion house Christian Dior.

Through a series of strategic acquisitions and investments, Arnault built LVMH into a leading company in the luxury industry, overseeing significant growth and expansion into various sectors, including fashion, jewelry, watches, and wine.

Despite controversies, including his attempt to become a Belgian citizen, Arnault's business acumen has solidified his status as a key figure in the global luxury market.

[6] His father, manufacturer Jean Léon Arnault, a graduate of École Centrale Paris, owned the civil engineering company Ferret-Savinel.

[6] Three years later, after he convinced his father to shift the focus of the company to real estate, Ferret-Savinel sold the industrial construction division and was renamed Ferinel.

[6][10] In 1984, Arnault, then a young real estate developer, heard that the French government was set to choose someone to take over the Boussac Saint-Frères empire, a textile and retail conglomerate that owned Christian Dior.

[12] With the help of Antoine Bernheim, a senior partner of Lazard Frères, Arnault acquired the Financière Agache, a luxury goods company.

[12] He sold nearly all of the company's assets, keeping only the Christian Dior brand and Le Bon Marché department store.

[13] He worked with Alain Chevalier, CEO of Moët Hennessy, and Henry Racamier, president of Louis Vuitton, to form LVMH in 1987.

The fault became too large to ignore when Arnault had a differing strategic vision from Henry Racamier, Louis Vuitton's president.

[13] That same year, he sponsored French fashion designer Christian Lacroix to advertise the company's luxury clothing line.

[15] LVMH acquired Berluti and Kenzo in 1993, the same year Arnault bought out the French economic newspaper La Tribune.

[24] That same year, Arnault turned his eyes to Gucci, an Italian leather goods company, which was run by Tom Ford and Domenico De Sole.

[30][31][32][33] On 7 March 2011, Arnault announced the acquisition of 50.4% of family-owned shares of the Italian jeweler Bulgari, to make a tender offer for the rest, which was publicly owned.

[36] On 7 March 2013, National Business Daily reported that mid-priced clothing brand QDA would open stores with the assistance of Arnault's private equity firm LCapitalAsia and Chinese apparel company Xin Hee Co., Ltd. in Beijing.

[36] In February 2014, Arnault entered into a joint venture with the Italian fashion brand Marco De Vincenzo, taking a minority 45% stake in the firm.

[40] By January 2018, Arnault had led the company to record sales of €42.6 billion in 2017, 13% over the previous year, as all divisions turned in strong performances.

[46] In late October 2020, Tiffany and LVMH agreed to the original takeover plan, though at a slightly reduced price of nearly $16 billion, a minor reduction of 2.6% from the aforementioned deal.

[16] Arnault has said that brands like Louis Vuitton and Dior are successful because "they have these two aspects, which may be contradictory: They are timeless, [and] they are at the utmost level of modernity.

[54] Alexandre is the EVP of Tiffany & Co., Frédéric is the CEO of LVMH Watches,[55] and Jean is the Director of Watchmaking Marketing and Development at Louis Vuitton.

[56] Since 2010, Arnault's daughter Delphine has been with Xavier Niel, a French billionaire businessman active in the telecommunications and technology industry.

In 2008, he established Protectinvest, a private foundation in Belgium set up to safeguard the integrity of the LVMH group until 2023; the foundation locked up the Arnault children's ability to sell shares in Pilinvest until 2023, by which time Arnault's youngest child turned 25, an age deemed old enough to assume responsibility for LVMH.

[61] In December 2011, six months before Socialist François Hollande took office as President of France, he transferred a 31 percent stake in Groupe Arnault – at the time considered by the newspaper Libération worth €6.5 billion – to Pilinvest.

[65] Arnault briefly surpassed Jeff Bezos to become the richest person in the world in December 2019,[66] and again for a short time in January 2020.

[71] In 2022, Arnault changed the legal structure of Agache from a Societas Europaea (SE) to a joint-stock partnership to ensure family control over LVMH in the long term.

Requesting Belgian nationality was to better protect the foundation that I created with the sole purpose of ensuring the continuity and integrity of the LVMH group if I were to die.

"[77] On 10 April 2013, Arnault announced he had decided to abandon his application for Belgian citizenship, saying he did not want the move to be misinterpreted as a measure of tax evasion, at a time when France faced economic and social challenges.

[86] The LVMH Young Fashion Designer was created as an international competition open to students from fine arts schools.