Gagaku (雅楽, literally "elegant music") is a type of Japanese classical music that has been performed at the Imperial Court in Kyoto for several centuries. It consists of three primary repertoires:

Gagaku, like shomyo, employs the yo scale, a pentatonic scale with ascending intervals of two, three, two, two, and three semitones between the five scale tones.

By the 7th century, the gakuso (a zither) and the gakubiwa (a short-necked lute) had been introduced in Japan from China. Various instruments including these two were the earliest used to play gagaku.

Gagaku, the oldest classical music in Japan, was introduced into Japan with Buddhism from the China. In 589, Japanese official diplomatic delegations were sent to China (during the Sui dynasty) to learn Chinese culture, including Chinese court music, Gagaku.

Komagaku and togaku arrived in South Japan during the Nara period (710-794), and settled into the basic modern divisions during the Heian period (794-1185). Gagaku performances were played by musicians who belonged to hereditary guilds. During the Kamakura period (1185-1333), military rule was imposed and gagaku was performed in the homes of the aristocracy, but rarely at court. At this time, there were three guilds based in Osaka, Nara and Kyoto.

Toshio Hosokawa (細川 俊夫, Hosokawa Toshio^?, born 23 October 1955 in Hiroshima, Japan) is a Japanese composer of contemporary classical music.

Hosokawa studied with Yun Isang at the Berlin University of the Arts. Since 1998, Hosokawa has served as Composer-in-Residence at the Tokyo Symphony Orchestra. In 2004, Hosokawa became a guest professor at Tokyo College of Music. In 2001, Hosokawa became a member of Akademie der Künste, Berlin.

Invited by Walter Fink, he was the 18th composer featured in the annual Komponistenporträt of the Rheingau Musik Festival in 2008, in chamber music, played by the Arditti Quartet and Mayumi Miyata (Shō), and the oratorio Voiceless Voice in Hiroshima, performed by the WDR Symphony Orchestra and Choir, Cologne conducted by Rupert Huber.

Hosokawa has received the following awards and honors.