Adventure therapy (AT) is defined as "the prescriptive use of adventure experiences provided by mental health professionals, often conducted in natural settings, that kinesthetically engage clients on cognitive, affective, and behavioral levels". Despite an increase in research and evaluation in recent years examining the relative effectiveness of AT for youth and young adults, little is known about the AT process. This study highlights the development and psychometric properties of the Adventure Therapy Experience Scale (ATES) for its potential use in identifying unique factors that are theoretically reasoned to be inherent in an AT experience. The results suggest the ATES is an appropriate instrument to use to assess how these four factors effectuate outcome, especially when used in conjunction with the routine outcome monitoring of treatment progress.