Harriell starred as Maria in a 1996 tour of the Broadway musical West Side Story and replaced Daphne Rubin-Vega as Mimi in the Broadway production of Rent. She made her Broadway debut on April 4, 1997. Harriell was also part of the ensemble in the short-lived Broadway musical Lennon, featuring the music of former BeatleJohn Lennon; it was written and directed by Don Scardino.
On television, Harriell has been seen in Queens Supreme, NCIS, Ed, and Law and Order. She was also featured in the film Grindhouse, in Quentin Tarantino's segment, Death Proof.
Harriell has been married to actor Robert Harriell since 1995.
Harriell landed the role of Mimi in the hit musical Rent on April 4, 1997, marking her Broadway debut. She performed in Rent until June 6, 1999. Her next Broadway credit was Lennon at the Broadhurst Theatre. She was last seen playing Vanessa in In the Heights, having taken over from Karen Olivo on November 18, 2008. She stayed with the role until the Broadway production closed on January 9, 2011