Margi Derks Peterson has been accompanying for ballet since 1976. She has played for numerous teachers from Grand Rapids, as well as guests and visitors from all over the world, including Edward Villella, Charles Askegard, Patricia Barker, Tom Gold, Charlie Neshyba-Hodges, and Mario Radacovsky. She has written a 35-minute ballet for the story of The Steadfast Tin Soldier, which has been recorded and subsequently performed several times by Grand Rapids' Creative Arts Repertoire Ensemble, with choreography and direction by Judy Genson. Margi works as a freelance musician, currently directing adult and children's choirs at East Congregational Church in Grand Rapids, accompanying at Grand Rapids Ballet, and teaching private voice lessons. She also directs a middle school choir for the Vocal Music Workshop. She composes and arranges for a variety of musical soloists and ensembles, and performs as a church soloist and in musical theatre. Margi also music directs for local theatres, including Circle Theatre, Robeson Players, Actors Theatre, and various high schools.