In 1959 Valentino left Paris and opened a fashion house in Rome on the posh Via Condotti with the backing of his father and an associate of his. More than an atelier, the premises resembled a real "maison de couture," it being very much along the lines of what Valentino had seen in Paris: everything was very grand and models flew in from Paris for his first show. Valentino became known for his red dresses, in the bright shade that became known in the fashion industry as "Valentino red."
On July 31 1960, Valentino met Giancarlo Giammetti at the Café de Paris on the Via Veneto in Rome. One of three children, Giammetti was in his second year of architecture school, living at home with his parents in the haut bourgeois Parioli section of Northern Rome. That day Giammetti gave Valentino a lift home in his Fiat and a friendship, as well as a long-lasting partnership, started. The day after, Giammetti was to leave for Capri for vacation and, by coincidence, Valentino was also going there, so they met again on the island 10 days later. Giammetti would shortly thereafter abandon the University to become Valentino's business partner. When Giammetti arrived, the business situation of Valentino's atelier was in fact not brilliant: in one year he had spent so much money that his father's associate pulled out of the business, and had to fight against bankruptcy. 
Valentino's international debut took place in 1962 in Florence, the Italian fashion capital of the time. His first show at the Pitti Palace was welcomed as a true revelation and the young couturier was deluged by orders from foreign buyers and enthusiastic comments on the press.
After the breakthrough show in Florence, Valentino began dressing the ladies of the international best-dressed crowd, such as his acquaintance from the Paris years Countess Jacqueline de Ribes and New York socialites Babe Paley and Jayne Wrightsman.
By the mid-1960s he was already considered the undisputed maestro of Italian Couture, receiving in 1967 the Neiman Marcus Fashion Award, the equivalent of an Oscar in the field of fashion. The Begum Aga Khan, Farah Diba, Jacqueline Kennedy Onassis, Lee Radziwill, Queen Paola of Belgium, Babe Paley, Elizabeth Taylor, Audrey Hepburn, Gloria Guinness, Marella Agnelli, Jayne Wrightsman, Marisa Berenson, Veruschka and Princess Margaret were already customers as well as personal friends.
At some point in 1964, Jacqueline Kennedy had seen Gloria Schiff, the twin sister of the Rome-based fashion editor of American Vogue and Valentino's friend Consuelo Crespi, wearing a two-piece ensemble in black organza at a gathering. It made such an impression that Kennedy contacted Ms. Schiff to learn the name of the ensemble's designer, which was Valentino. In September 1964, Valentino was to be in the United States to present a collection of his work at a charity ball at New York's Waldorf-Astoria Hotel. Mrs. Kennedy wanted to view the collection but could not attend the event, so Valentino decided to send a model, sales representative and a selection of key pieces from his collection to Mrs. Kennedy's apartment on Fifth Avenue. Mrs. Kennedy ordered six of his haute couture dresses, all in black and white, and wore them during her year of mourning following President John F. Kennedy's assassination. From then on, she was a devoted client and would become a friend. Valentino would later design the white dress worn by Kennedy at her wedding to Greek tycoon Aristotle Onassis.
In 1966, confident of his client base, he moved his shows from Florence to Rome where two years later he achieved one of his greatest triumphs, an all-white collection that became famous for the "V" logo he designed.
Throughout the 1970s Valentino spent considerable time in New York City, where his presence was embraced by society personalities such as Vogue's editor-in-chief Diana Vreeland and the art icon Andy Warhol.
From 1983 through 1985, the Ford Motor Company offered a Valentino Edition of its Continental sedan. It featured various color changes during this time and offered features that were optional on the standard model.
The year 1990 marked the opening of the Accademia Valentino, designed by architect Tommaso Ziffer, a cultural space located near Valentino's atelier in Rome, for the presentation of art exhibitions. The next year, encouraged by their friend Elizabeth Taylor, Valentino Garavani and Giancarlo Giammetti created L.I.F.E., an association for the support of AIDS-related patients, which benefits from the activities of the Accademia Valentino. 
In 1998 Valentino and his partner Giancarlo Giammetti sold the company for approximately US$300 million to HdP, an Italian conglomerate controlled, in part, by the late Gianni Agnelli, the head of Fiat. In 2002, Valentino S.p.A., with revenues of more than $180 million, was sold by HdP to Marzotto Apparel, a Milan-based textile giant, for $210 million.
On September 4 2007, Valentino announced that he would retire fully in January 2008. from the world stage after his last haute couture show in Paris. He delivered his last women's ready-to-wear show in Paris on 4 October.
His last haute couture show was presented in Paris at the Musée Rodin on January 23, 2008. It was, however, somewhat marred by his criticism of fellow Italian design duo Dolce & Gabbana, and the death of Australian actor Heath Ledger although few allowed these things to detract from his final show, which received a standing ovation from the entire audience that included hundreds of notable names from all areas of show business. Many models returned to show for Valentino's last haute couture show, including Eva Herzigova, Naomi Campbell, Claudia Schiffer, Nadja Auermann, Karolina Kurkova and Karen Mulder.
The Valentino Garavani Virtual Museum
The Valentino Garavani Virtual Museum is a downloadable desktop application that digitally displays the 50 year archive of Italian fashion designer Valentino Garavani. This application uses real time 3D technology is to create an immersive environment within the app. It connects to online media database that displays over 5,000 images including sketches, illustrations, advertising campaigns, editorials, red carpet moments and 180 fashion show videos. Content is arranged in a museum layout where users explore the different galleries and wings covering what would be over 10,000 square meters in an actual museum.
The museum became available for download on December 5, 2011 at www.valentino-garavani-archives.org. The Valentino Garavani Virtual Museum was created by Valentino's long-time partner Giancarlo Giammetti. It was designed and produced by Novacom Associés-Paris, in collaboration with Kinmonth-Monfreda Design Project – London. <
Valentino: Master of Couture Exhibition, 29 November 2012 - 3 March 2013
This major new exhibition opening at Somerset House in London celebrating the life and work of Valentino will showcase over 130 exquisite haute couture designs worn by icons such as Jackie Kennedy Onassis, Grace Kelly, Sophia Loren and Gwyneth Paltrow in an exciting specially created installation.
Divided into three sections; visitors will start with a private view of Valentino's world through photographs from his personal archive, offering an intimate portrait of the life of the master. The exhibition then unfolds into a couture fashion show where roles are reversed with visitors walking the catwalk to view a staggering one hundred and thirty Valentino haute couture designs.
The final section will unpick the painstaking processes of crafting couture exemplified by the stunning wedding dress of Princess Marie Chantal of Greece, demonstrating the beauty of the work of les petit mains who sew each stitch by hand. In addition a specially commissioned group of films will allow behind-the scenes access to the Valentino atelier, where the craft of couture is demonstrated in a series of fascinating samples. Finally, discover more about the man, the icon, by exploring the Valentino Garavani Virtual Museum.
There will be a series of talks, screenings and events to accompany the exhibition.