Merrill Ashley was born in St. Paul, Minnesota, in 1950. She studied at the School of American Ballet and joined the New York City Ballet in 1967. She was appointed soloist in 1974 and principal in 1977. One of the last ballerinas to be trained by Balanchine. Known for her brilliant, dynamic allegro, precision, and musicality.
Balanchine created two showcase roles for her in Ballo della Regina (1977) and Ballade (1980). He also revived Four Temperaments and Square Dance especially for her in 1976.
Between 1969 and 1973 she toured the US with a small company headed by d'Amboise and between 1980 and 1981 she was director and dancer with her own group, Merrill Ashely and Dancers. She retired from the stage in 1997, setting a record as the dancer with longest career at NYCB.