The present study extends previous research on acceptance and commitment therapy (ACT) by using a new ACT protocol, the Fusion Management System (Dixon, 2013 in press) with a new population. Participants were 2 high functioning children with autism: an 8-year old boy and a 12 year-old girl. Using a multiple baseline design, 2 participants were exposed to 15 hours of therapy over the span of 12 weeks. Behavioral data was taken for each participant by their parent(s) on a problematic behavior that was of concern to them. Prior to and following the ACT intervention, both participants took three psychometric measures that were designed to measure ACT related processes: the Child and Adolescent Mindfulness Measure (CAMM), the Acceptance and Action Questionnaire-II (AAQ-II), and the Avoidance and Fusion Questionnaire for Youth (AFQ-Y). Following the intervention one participant improved on all measures of the ACT related processes and the other participant's score improved on the AFQ-Y and slightly deteriorated on the CAMM and AAQ-II. During the intervention phase of this study both participants' problematic behavior significantly improved. Implications of the study and future research are also discussed.