The ongoing evaluation of Training for Adoption Competence (TAC) has established a substantial body of evidence that TAC is an effective training model that increases knowledge and influences clinical practices in ways consistent with specified learning objectives. The logical next step – beyond confirming TAC is an effective model of training — was to test TAC’s theory of change by studying the effects of TAC on the quality and effectiveness of clinical services in real-world settings, collecting data from adoptive families about their treatment experiences and outcomes. That study was completed in 2020 using data from 89 adoptive families treated by 34 TAC-trained clinicians and 70 adoptive families treated by 36 comparably qualified clinicians who were not TAC-trained.