Mills has danced principal roles in the George Balanchine repertoire as well as works by Choo-San Goh, John Butler, Ohad Naharin, Vicente Nebrada, Domy Reiter-Soffer and Mark Dendy.
In 1998, Mills was chosen to represent the United States through his work, Ashes, at Les Rencontres Chorégraphiques Internationales de Seine-Saint-Denis in Paris.
The work was imagined as a way for art, specifically dance, to convene a broad conversation about The Holocaust and contemporary issues of genocide and human rights.
According to an archived article by the Huffington Post, “Mills created the confrontational, distinctly contemporary ballet in 2005 after spending 18 months researching the Holocaust, when Germany's Nazi party exterminated more than 6 million Jews during World War II.
The ballet is set to contemporary music by Steve Reich, Evelyn Glennie, Michael Gordon, Arvo Part and Philip Glass.