Susumu Hirasawa (平沢 進, born April 1, 1954), nicknamed "Hirasawa" (ヒラサワ) and "Shishō" (師匠), is a Japanese music artist and composer.
In the fifth year of elementary school, Hirasawa took up the electric guitar, inspired by the surf and instrumental rock bands he heard on the radio and on TV, later joining his junior high school's band. In 1973 he formed Mandrake, a progressive rock band that incorporated elements from heavy metal and krautrock. One of the few Japanese progressive rock bands of its time, Mandrake achieved little success and released no albums during its lifetime. After discovering punk rock and working on synthesizer-heavy projects, Hirasawa felt that progressive rock became just entertainment and decided to reform the band as an electropunk unit.
In January 1, 1979, Mandrake became the new wave/electronic rock band P-Model. Originally a commercially successful band—with the albums In a Model Room and Landsale considered hallmarks of Japanese technopop—they turned to decidedly uncommercial post-punk and experimental rock after Hirasawa went through an averse reaction to his fame. The band went through various lineups, all led by Hirasawa, and achieved some popularity on the Japanese independent music scene. The group released eight albums during this run, and kept operating until 1988, when Hirasawa decided to "freeze" it.