he shakuhachi (尺八 (しゃくはち)?, pronounced [ɕakɯhatɕi]) is a Japanese end-blown flute. Its name means "1.8 Shaku", referring to its size. It is traditionally made of bamboo, but versions now exist in ABS and hardwoods. It was used by the monks of the Fuke school of Zen Buddhism in the practice of suizen (吹禅?, blowing meditation). Its soulful sound made it popular in Western 1980s pop music.

They are often made in the minor pentatonic scale.

The bamboo flute first came to Japan from China via Korea. The shakuhachi proper, however, is quite distinct from its Chinese counterpart[1] – the result of centuries of isolated evolution in Japan.

During the medieval period, shakuhachi were most notable for their role in the Fuke sect of Zen Buddhist monks, known as komusō ("priests of nothingness," or "emptiness monks"), who used the shakuhachi as a spiritual tool. Their songs (called "honkyoku") were paced according to the players' breathing and were considered meditation (suizen) as much as music.

Travel around Japan was restricted by the shogunate at this time, but the Fuke sect managed to wrangle an exemption from the Shogun, since their spiritual practice required them to move from place to place playing the shakuhachi and begging for alms (one famous song reflects this mendicant tradition, "Hi fu mi, hachi gaeshi", "One two three, pass the alms bowl"). They persuaded the Shogun to give them "exclusive rights" to play the instrument. In return, some were required to spy for the shogunate, and the Shogun sent several of his own spies out in the guise of Fuke monks as well. This was made easier by the wicker baskets that the Fuke wore over their heads, a symbol of their detachment from the world.

In response to these developments, several particularly difficult honkyoku pieces, e.g., Shika no tone, became well-known as "tests": if you could play them, you were a real Fuke. If you couldn't, you were probably a spy and might very well be killed if you were in unfriendly territory.

With the Meiji Restoration, beginning in 1868, the shogunate was abolished and so was the Fuke sect, in order to help identify and eliminate the shogun's holdouts. The very playing of the shakuhachi was officially forbidden for a few years. Non-Fuke folk traditions did not suffer greatly from this, since the tunes could be played just as easily on another pentatonic instrument. However, the honkyoku repertoire was known exclusively to the Fuke sect and transmitted by repetition and practice, and much of it was lost, along with many important documents.

When the Meiji government did permit the playing of shakuhachi again, it was only as an accompanying instrument to the koto, shamisen, etc. It was not until later that honkyoku were allowed to be played publicly again as solo pieces.

Shakuhachi has traditionally been played almost exclusively by men in Japan, although this situation is rapidly changing. Many teachers of traditional shakuhachi music indicate that a majority of their students are women. The 2004 Big Apple Shakuhachi Festival in New York City hosted the first-ever concert of international women shakuhachi masters. This Festival was organized and produced by Ronnie Nyogetsu Reishin Seldin, who was the first full-time Shakuhachi master to teach in the Western Hemisphere. Nyogetsu also holds 2 Dai Shihan (Grand Master) Licenses, and has run KiSuiAn , the largest and most active Shakuhachi Dojo outside Japan, since 1975.