Benois de la Danse laureate Benois de la Danse nominee
Hallberg attended American Ballet Theatre's New York Summer Intensive in 1999 and 2000 and was an ABT National Training Scholar in 1999 and 2000.
Hallberg joined ABT's Studio Company in September 2000 and then joined American Ballet Theatre as a member of the corps de ballet in April 2001. His roles with the Company include Espada in Don Quixote, the second sailor in Fancy Free, the Cavalier in The Nutcracker, a Friend of the Family in Pillar of Fire, Benvolio in Romeo and Juliet, Benno in Swan Lake and leading roles in Sir Frederick Ashton's Symphonic Variations and the first movement in George Balanchine's Symphony in C and Theme and Variation. He also performed featured roles in William Forsythe's workwithinwork and Stanton Welch's Clear. He created the title role in Robert Hill's Dorian.
Hallberg was a recipient of the Princess Grace Fellowship and the Chris Hellman Dance Award for 2002-2003.
Hallberg was appointed a Soloist effective January 2004.