Yairi is the surname of a Japanese family of luthiers including Sadao Yairi who made guitars under the S.Yairi brand. His son Hiroshi Yairi made acoustic guitars under Sadao's supervision (usually signed and/or stamped as by S.Yairi). Sadao was uncle of Kazuo Yairi who built guitars mostly under his own brand, K. Yairi. In the 1960s to early 1970s some guitars were been branded just Yairi or Yairi Gakki.