Maltreatment that occurs during childhood impacts on the development and maturation of the individual throughout his or her life. The application of an ecosystemic play therapy approach to working with children who have been maltreated was the focus of this practicum. The practicum experience included seeing children on a weekly basis for a year to help them with issues related to the experiences of maltreatment. A review of the literature regarding issues related to abuse and trauma in children and play therapy is provided. Three case examples are described in this report including an analysis of the results of standardized measures. Clinical themes relevant to working with maltreated children using an ecosystemic play therapy approach are discussed and include: assessment, the therapeutic relationship, development of the child, attachment, loss, and defense mechanisms.