For the first performance in Paris, Klein invited three naked women, whom he called "living brushes", who "covered themselves in his signature deep blue paint and pressed their bodies on paper during the sound half of the symphony, freezing during the silence".

Parodying a traditional catalogue raisonné, the book featured a series of intense monochromes linked to various cities he had lived in during the previous years.

From the reactions of the audience, [Klein] realized that...viewers thought his various, uniformly colored canvases amounted to a new kind of bright, abstract interior decoration.

Shocked at this misunderstanding, Klein knew a further and decisive step in the direction of monochrome art would have to be taken...From that time onwards he would concentrate on one single, primary color alone: blue.

Discovered with the help of Edouard Adam, a Parisian paint dealer,[12] the optical effect retained the brilliance of the pigment which, when suspended in linseed oil, tended to become dull.

[17] For his next exhibition at the Iris Clert Gallery (April 1958), Klein chose to show nothing whatsoever, called La spécialisation de la sensibilité à l'état matière première en sensibilité picturale stabilisée, Le Vide (The Specialization of Sensibility in the Raw Material State into Stabilized Pictorial Sensibility, The Void): he removed everything in the gallery space except a large cabinet, painted every surface white, and then staged an elaborate entrance procedure for the opening night: the gallery's window was painted blue, and a blue curtain was hung in the entrance lobby, accompanied by republican guards and blue cocktails.

[18] The art historian Olivier Berggruen situates Klein "as one who strove for total liberation," forming connections between perverse ritual and a disdain of convention.

[19] According to Berggruen, he used ritual as a means not to attain belief, but rather as a forum through which to reach abstraction—transcending worldly vestiges temporarily, and returning to earth as a new being.

Recently my work with color has led me, in spite of myself, to search little by little, with some assistance (from the observer, from the translator), for the realization of matter, and I have decided to end the battle.

Klein celebrated the commission by travelling to Cascia, Italy, to place an ex-voto offering at the Saint Rita Monastery.

Klein's last two exhibitions at Iris Clert's were Vitesse Pure et Stabilité Monochrome (Sheer Speed and Monochrome Stability), November 1958, a collaboration with Jean Tinguely, of kinetic sculptures, and Bas-Reliefs dans une Forêt d'Éponges (Bas-Reliefs in a Sponge Forest), June 1959, a collection of sponges that Klein had used to paint IKB canvases, mounted on steel rods and set in rocks that he'd found in his parents' garden.

Sometimes the creation of these paintings was turned into a kind of performance art—an event in 1960, for example, had an audience dressed in formal evening wear watching the models go about their task while an instrumental ensemble played Klein's 1949 The Monotone Symphony.

Klein created a composite photograph, Saut dans le vide (Leap into the Void),[24] originally published in his 1960 artist's book Dimanche, which apparently shows him jumping off a wall, arms outstretched, towards the pavement.

In fact, "Saut dans le vide", published as part of a broadside on the part of Klein (the "artist of space") denouncing NASA's own lunar expeditions as hubris and folly, was a photomontage in which the large tarpaulin, held by artist friends, Klein leaped onto was removed from the final image.

Founding members were Arman, Francois Dufrêne, Raymond Hains, Yves Klein, Martial Raysse, Daniel Spoerri, Jean Tinguely, and Jacques Villeglé, with Niki de Saint Phalle, Christo and Gérard Deschamps joining later.

Normally seen as a French version of Pop Art, the aim of the group was stated as 'Nouveau Réalisme—new ways of perceiving the real' [Nouveau Réalisme nouvelles approches perceptives du réel].

[26] A large retrospective was held at Krefeld, Germany, January 1961, followed by an unsuccessful opening at Leo Castelli Gallery, New York, in which Klein failed to sell a single painting.

I have the deep feeling that there exists in the very essence of bad taste a power capable of creating those things situated far beyond what is traditionally termed "The Work of Art."

[27]He moved on to exhibit at the Dwan Gallery, Los Angeles, and traveled extensively in the Western U.S., visiting Death Valley in the Mojave Desert.

[28] A sort of parody of Klein's Anthropometry performance is featured in the 1961 film Wise Guys (original title: Les Godelureaux) directed by Claude Chabrol.

[29] On 8 December 2017, Welsh alternative rock band Manic Street Preachers released the lead single from their thirteenth studio album Resistance is Futile, International Blue.

"[30] In 2017, the MoMA- and WNYC-produced contemporary art podcast A Piece of Work hosted by Abbi Jacobson had an episode focused on Klein's blue monochromes.

Alongside works by Andy Warhol and Willem de Kooning, Klein's painting RE 46 (1960) was among the top-five sellers at Christie's Post-War and Contemporary Art sale in May 2006.

[35] The record for the most expensive of his paintings was reached by Le Rose du Bleu (RE 22), who sold by $36,753,200 at Christie's London, on 27 June 2012.