Mohammad-Rezā Shajariān(Persian: محمدرضا شجريان) (born September 23, 1940 in Mash'had, Iran; died October 8, 2020 in Tehran) was a legendary and critically acclaimed Persian traditional singer, composer and Ostad (master) of Persian music. During his life he was called "Iran's greatest living master of Persian Classical music". In Persian classical Dastgah music, singing is the most difficult art to master and Shajarian is the embodiment of the perfect singer and a major source of inspiration.