Mary Elizabeth Sell was born in Wilton, Connecticut, and began her dance training at the age of five.  Ms. Sell entered the School of American Ballet (SAB), the official school of New York City Ballet, in the fall of 1996.  While a student at SAB, Ms. Sell performed with the Company in Coppelia, Scherzo alla Russe, and Double Feature.  Ms. Sell originated a corps role in Christopher d'Amoise's Tribute, as part of the SAB 2005 Annual Workshop. 

In December 2005, Ms. Sell became an apprentice with NYCB, and in September 2006 she joined the Company as a member of the corps de ballet.