Some children with autism spectrum disorders (ASD) are intensely affected by separation and changes in therapy. They tend to display varying degrees of difficulties in dealing with holidays, breaks and the closure of music therapy. This difficulty is often intensified when the child is strongly attached to the therapist and has precarious awareness of what ending means, and yet lacks the capacity for emotional self-regulation. Preparing children for parting might bring about excessive anxiety, overwhelming distress and even the fear of death and dying that the child finds difficult to contain or to articulate in words.This article explores and examines clinical phenomena and issues of ending in improvisational music therapy with children with ASD and how the difficulty is addressed, contained and transformed in spontaneous interaction (both musical and non-musical), between the therapist and the child. In order to enhance a better understanding of the phenomena of endings, some fundamental aspects of the mutual music making process in music therapy and its consequences in the therapeutic relationship are described and linked to issues of endings in different stages of music therapy. The role of the music and the therapist in helping the child to cope with endings in music therapy will be discussed in depth through clinical vignettes within the psychodynamic perspectives.