Marjon Halmeyer-Roos was born in the Netherlands but grew up in Brazil, which laid the foundation for her career as a Music Therapist. Her youth was marked by the rich Brazilian music that directed her path toward a career in Music Therapy. She graduated from the HAN University of Applied Sciences in Music Therapy and began her career at the Sophia Children’s Hospital in Rotterdam, where she specialized in the methodical application of music as a therapeutic tool for children with autism spectrum disorders. This experience shaped her through the specific neurological interventions required in the treatment of her clients. She later joined the Expertise Center of the Driestroom Foundation in Arnhem-Nijmegen and worked in two nursing homes in that region. In 2005 she moved with her husband to Curaçao, where she worked at the Foundation for Parental Support for Children with Disabilities (SOKH). In 2011 she founded the Music Therapy Center Curaçao, where she serves as director. The therapy center offers various Music Therapy and Arts Therapies services. MTCC provides services such as Music Therapy treatments to GGZ Curaçao (Mental Health Care). She has experience in Music Therapy within addiction care and collaborates with a psychologist in various neuropsychological fields. Marjon further specialized in Neurological Music Therapy and its methodology Neuromusica y Neurohabilitacion, Red Iberoamericana de Musicoterapia y Neurociencias en Argentina.
In addition to providing treatments through music therapy, she has also trained in communication skills and provides supervision to students of Arts Therapies. Halmeyer-Roos holds the position of chairperson at the Caribbean Association of Arts-Play and Psychomotor Therapists (CAAPPT) and is also co-founder and project manager at United Through Music Curaçao Foundation, an organization that promotes music in healthcare with the aim to connect people.