Introduction Chronic maltreatment and disorganized attachment in children predict the development of dissociation, which can negatively impact functioning. Few measures of child dissociation currently exist and amongst these, limitations exist when they are applied to populations of maltreated children. Objective This paper details the development of the Child Dissociation Assessment System (CDAS), consisting of the Child Dissociation Code (CDC) and Child Dissociation Tool (CDT). The CDC allows clinicians to screen for dissociative symptoms while the CDT examines how these symptoms impact different domains of functioning. Method Both measures score verbal and non-verbal material, which emerges during the MacArthur Story Stem Battery (MSSB), a child-friendly narrative story stem task whose non-threatening nature is suited for use with maltreated children. Using the CDAS, the MSSB protocols of 20 children between 6 and 12 years old (10 from a clinical sample and 10 from a non-clinical sample) were scored. Results The CDAS possesses adequate to excellent inter-rater reliability, and the CDC discriminates between maltreated and non-maltreated children. Conclusion The CDAS may be of interest for researchers and clinicians working with populations of maltreated children. Preliminary findings are promising and a larger-scale validation would be indicated.