There are few studies of the child psychodynamic psychotherapy process. This study investigates the psychotherapy process within regulation-focused psychotherapy for children (RFP-C; Hoffman, Rice, & Prout, 2016). RFP-C is a manualized, psychodynamic treatment for children with disruptive behaviors. Three expert clinicians used the Child Psychotherapy Q-Set to develop an RFP-C prototype, which can be used in future studies to measure adherence in actual RFP-C sessions. As expected, the RFP-C prototype was associated with established prototypes of child psychodynamic psychotherapy and child-centered play therapy. There was no relationship between RFP-C and the cognitive behavior therapy process prototype. Reflective functioning was also associated with the RFP-C prototype, providing additional evidence for mentalization as a common factor in child psychotherapy. Implications for clinical practice and future research use are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved)