Although she never adopted a Russian stage name, Sono Osato made her reputation as a ballerina with Wassily de Basil's Ballets Russes (nicknamed 'Nonotchka' by other members of the troupe). She was born in Omaha, of mixed ethnic parentage: her father Shoji was a Japanese photographer, her Irish-French Canadian mother an aspiring actress of somewhat Bohemian temperament. Strong-willed, (Agnes de Mille described her as "brave and sweet, but nobody's fool"), Osato knew what she wanted to become after seeing Léonide Massine dance in "Cleopatre". After a period of intense training in Chicago, her tutor and mentor (ex-ballerina Berenice Holmes) set up an audition in Monte Carlo and Osato was able to join the Ballet Russe at the age of 14 (at the time, the youngest dancer to perform with the company, paid just $25 a week). Though performing in ballerina roles for six years, she was not promoted to premier danseuse nor did she receive the pay that was consummate to leading roles. Frustrated, she quit and joined the (American) Ballet Theater where she became a star of modern ballet, recipient of a Donaldson Award as best female dancer for her performance in the 1943 Broadway production of "One Touch of Venus" (choreographed by De Mille). Between December 1944 and February 1946, she headlined as Ivy Smith, the original 'Miss Turnstiles', in "On the Town" (the part famously played by Vera-Ellen in the 1949 MGM musical).

There were other shows and some television appearances, even a film role in the kitsch musical The Kissing Bandit (1948) with Frank Sinatra. Then, her career took a downturn in the aftermath of Japan's attack on Pearl Harbour. Though her brother served with the U.S. Army in Italy, her father was interned as an enemy alien and Osato herself became the target of racial bias. She was eventually forced to adopt her mother's maiden name and perform as Sono Fitzpatrick. In addition, the federal government barred her from touring with the Ballet Theater in California and Mexico. She later found herself on the HUAC blacklist after addressing a gathering of refugees from Franco's Spain and stopped dancing altogether by the end of the 1950s. Sono Osato spent her remaining years in New York. She was married to the Moroccan architect and entrepreneur Victor Elmaleh. In 2006, she set up the Sono Osato Scholarship Program for Graduate Studies at Career Transition For Dancers. Her autobiography, Distant Dances, was published in 1980.