After completing studies in composition in the USA, Mist embraced Icelandic musical life, teaching and being active in various artistic organizations as well as composing.  She has received commissions and grants from performers and organizations in America and Europe.

In 2001 Mist Thorkelsdottir, founded the Music Department of the Iceland Academy of the Arts and was Dean of Music until 2014. From 2014 – 2016 she was the Head of the Academy of Music and Drama of the University of Gothenburg. She has been a member of the board of the Association of Nordic Music Academies since 2002 and was a council member of the European Association of Music Conservatories (AEC) between 2006 - 20012.  She was a founding-  and board member of MusiQuE, European Quality Enhancement and Accreditation Agency for higher music education through 2016.

In July 2016 Mist came to the University of Southern California’s Thornton School of Music as Senior Advisor to the Dean on International Relations, designing and developing international programs for the school.

In August 2017 Mist joined the USC Office of Global and Strategic Initiatives, heading the international programs for the performing arts at the University of Southern California.  In 2022, she retired from USC and has since been a repeating Visiting Faculty member at the College of Music, Mahidol University in Bangkok, Thailand.