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The Gutai group (具体； means "Embodiment") is the first radical, post-war group in Japan. It was founded by the painter Jiro Yoshihara in Osaka, Japan, 1954, in response to the reactionary artistic context of the time. This influential group known as Gutai Bijutsu Kyokai was involved in large-scale multimedia environments, performances and theatrical events. According to the official website of Shozo Shimamoto, Shimamoto and Yoshihara founded Gutai together in 1954, and it was Shimamoto who suggested the name Gutai, which contrary to popular belief does not mean concrete but embodiment (according to this source) ”The kangi used to write 'gu' means tool, measures, and a way of doing something, while 'tai' means body.
In 1956, Yoshihara wrote the manifesto for Gutai group. Among its preoccupations, the manifesto expresses a fascination with the beauty that arises when things become damaged or decayed. The process of damage or destruction is celebrated as a way of revealing the inner "life" of a given material or object:
"Yet what is interesting in this respect is the novel beauty to be found in works of art and architecture of the past which have changed their appearance due to the damage of time or destruction by disasters in the course of the centuries. This is described as the beauty of decay, but is it not perhaps that beauty which material assumes when it is freed from artificial make-up and reveals its original characteristics? The fact that the ruins receive us warmly and kindly after all, and that they attract us with their cracks and flaking surfaces, could this not really be a sign of the material taking revenge, having recaptured its original life?...." 
In addition to Yoshihara and Shimamoto, members of the Gutai group included Takesada Matsutani, Sadamasa Motonaga fr:Sadamasa Motonaga, Atsuko Tanaka, Akira Kanayama, and others. A formative influence on the later Fluxus movement, the group was also associated with certain European (particularly French) art world figures such as Georges Mathieu and Michel Tapié, and with tachisme ("art informel"). According to the Tate Gallery's online art glossary, Gutai artists also "created a series of striking works anticipating later Happenings and Performance and Conceptual art."  Gutai artists also created works that would now be called installations, inspiring the work of non-Japanese artists such as Allan Kaprow, Nam June Paik, Wolf Vostell, and Conrad Bo, and leading to the later Fluxus network.
The Tate article records that "the group dissolved in 1972 following the death of Yoshihara."
From February 15 to May 8, 2013, the Solomon R. Guggenheim Museum presented Gutai: Splendid Playground, a retrospective of the Gutai Art Association (1954–72), the radically inventive and influential Japanese art collective whose innovative and playful approaches to installation and performance yielded one of the most important international avant-garde movements to emerge after World War II. Based on fifteen years of research, Gutai: Splendid Playground provided a critical examination of both iconic and lesser-known examples of the collective's dynamic output over its two-decade history and explored the full spectrum of Gutai’s creative production: painting, performance, installation art, sound art, experimental film, kinetic art, light art, and environment art. “Gutai: Splendid Playground” is the first large, in-depth exhibition devoted to Gutai and the first to thoroughly cover its panoply of mediums.
Comprising approximately 145 works by 25 artists and spanning two generations of Gutai artists, Gutai: Splendid Playground was organized into six chronological and thematic sections presented along the Guggenheim ramps:
The exhibition also included documentary films of the group’s historic outdoor exhibitions and stage events and offered a focus on their eponymous journal as a platform for international artistic exchange. A centerpiece of Gutai: Splendid Playground was a site-specific commission of Work (Water) (1956/2011) by the late Motonaga Sadamasa. Prior to his death in 2011, Motonaga reimagined his iconic early Gutai outdoor installation, made of plastic tubes filled with colored water, for the Guggenheim rotunda. Sixteen tubes stretched across the rotunda, greeting visitors with "jewel-like dollops of water tinted red, yellow blue or green." 
Gutai: Splendid Playground was co-curated by Ming Tiampo, Associate Professor of Art History, Carleton University, Ottawa, and Alexandra Munroe, Samsung Senior Curator of Asian Art, Solomon R. Guggenheim Museum. Assistance was provided by Asian Art Curatorial Fellow Lyn Hsieh.