Mohammad-Reza Shajarian (Persian: محمدرضا شجريان, 23 September 1940 – 8 October 2020) was an Iranian singer and master (Ostad) of Persian traditional music. He was also known for his skills in Persian calligraphy and humanitarian activities. Shajarian started his singing career in 1959 at Radio Khorasan, rising to prominence in the 1960s with his distinct singing style.