An important contributor to this field of work is Richard Schwartz, Ph.D. who developed his own therapeutic approach called The Internal Family Systems Model (IFS) over the past 20 years. It combines systems thinking with the view that the mind is made up of parts of self each with its own viewpoint and qualities.
Both of these approaches involve helping the client to understand that their external world is really just a reflection of their inner world. If one wants her/his life to be different, then she/he has to look within to find answers and make changes. EMDR is an ideal tool to help clients to create internal associations to overcome acute and chronic symptoms of trauma.