Leslie O'Neill began her dance training at the University of Wisconsin at Green Bay as a member of the Fighting Phoenix Dance Team. After two years, she transferred to the University of Minnesota-Twin Cities to continue her training in the hopes of becoming a professional where she had the opportunity to work with artists Doug Elkins, Shouze Ma, Judith Howard, and to perform in master works by Paul Taylor. She completed her BFA and went on to dance for local choreographers Ray Terrill, Rosy Simas, Maggie Bergeron, as well as Oregon-based Robin Stiehm. In 2005 Leslie joined Carl Flink as a founding member of Black Label Movement, where she honed her technique and began to find her voice as a performer. 

Leslie began making her own work in 2005, which first presented in the Minneapolis Fringe Festival. She also presented a solo, "Trigger," which she premiered at the Red Eye Works-In-Progress series, and later was performed by Emilie Plauche-Flink, artistic director of Black Label Movement, in their season "Fieldsongs" at the Southern Theater in 2009. Leslie joined Zenon Dance Company in 2006 as an apprentice and is now enjoying her 6th season as a company member. 

Leslie's most recent choreographic endeavors include "Tri," a trio for the scholarship students at Zenon's Dance Zone, and a recent presentation of her solo "These Years," for the Minneapolis Fringe Festival.  Leslie was nominated a Sage Award  2009 for her performance in BLM's Fieldsongs and Zenon Dance Company's spring season, and her solo "Trigger" was mentioned in "Top 5 Dance Events of 2009" in the Star Tribune.  Leslie is a 2010 recipient of the McKnight Fellowship for Dancers.