The development and factor analysis of the Adventure Therapy Experience Scale (ATES) is the first attempt found in the literature to empirically and quantitatively identify therapeutic factors theorized to affect change in the adventure therapy experience (Russell & Gillis, 2017). This study utilizes the ATES to explore how its inherent factors may impact treatment outcome utilizing a routine outcome monitoring process to empirically test how these factors may contribute to treatment outcome over time. The sample of 168 males 21.5 years of age completed an average of 79.6 days in the 90-day adventure-based substance use disorder residential treatment program. In the model, adventure-based experiences are a primary treatment tool. For outcome monitoring, all clients were administered the Outcome Questionnaire (OQ-45.2) at intake, every 2 weeks, and at discharge. In addition, clients were administered the 18-item ATES every 2 weeks. The ATES contains 2 items measuring how helpful the adventure experience was as well as how mindful they were of their treatment process during the experience. Clients also answer 16 Likert items measuring responses on 4 subscales: group adventure, nature, challenge, and reflection. Results reveal that clients, on average, improved in their psycho-social functioning as measured by the OQ 45.2. Weeks with higher helpfulness, mindfulness, and group adventure scores than the client’s average helpfulness, mindfulness, and group adventure score, had greater decreases in OQ scores than weeks with lower helpfulness, mindfulness, and group adventure scores. Clients with higher aggregate helpfulness and group adventure scores, across all treatment weeks, had greater decreases in OQ scores than clients with lower aggregate helpfulness and group adventure scores. Implications for practice and future research are also discussed.