Reflective Network Therapy (RNT) is a psychoanalytical and systemically-informed therapy approach providing early intervention in the classroom for preschool children diagnosed with Autism Spectrum Disorder and Pervasive Developmental Disorder, as well as those with Post-Traumatic Stress Disorder. While research has been conducted to assess RNT's potential benefits, the majority of findings remain limited regarding how clinicians can understand therapeutic progress and regarding which tools to use to formally assess children enrolled in RNT. The Behavioral Observation Inventory for Children (BORSC) was developed as a tool for assessing changes for children engaging in this treatment and for helping clinicians to review changes in children's behaviors over time. This quantitative research study analyzed an archival data set of previous BORSC ratings for videotaped RNT sessions of four preschool-aged children, at two intervals several months apart, so as to assess the inter-rater reliability of the BORSC, and therefore, its ability to show changes over time. Using Krippendorff's Alpha Coefficient, results did not show statistically significant similarities between raters and interrater reliability could not be established for the current version of the BORSC. However, using an Intraclass Correlation Coefficient showed greater inter-rater agreement, but not at levels that reached statistical significance. In its current form, the BORSC was determined to lack clear operationalization and limited statistical properties, whereby the findings obscure assessing change over time for RNT. Therefore, recommendations were made for revising the BORSC, (BORSC-2), as well as for expanding on the tool's psychometric properties, in order to guide future research. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]