He had only a brief performing career, making his debut with the Brooklyn Lyric Opera at the age of eighteen and appearing in summer stock productions.
For Pennsylvania Ballet he taught daily and re-staged several of his well-known ballets-Madrigalesco, Recital for Cello and 8 Dancers, Grand Pas Espagnol plus created several new works including Quartet, Time Passed Summer, Continuum, Four Men Waiting, From Gentle Circles, Signatures and Poems of Love and the Seasons.
He also brought in choreographers including Hans van Manen, Charles Czarny, Margo Sappington, Lynne Taylor-Corbett, Rodney Griffin, Choo San Goh, to create works for the company.
During this period, Harkarvy helped to raise the profile of the Philadelphia-based troupe, but he left in 1982 after the company began to experience severe financial difficulties.
As director of the Juilliard's Dance Division from 1992, Harkarvy expanded existing programs and created innovative new ones, remaining with the school until the time of his death.