Athletic trainers (ATs) are healthcare professionals who are responsible for the prevention, emergency care, clinical diagnosis, therapeutic intervention and rehabilitation of injuries and medical conditions in the physically active.1 Part of an AT’s knowledge and skill set involves recognition and care of exertional heat illness EHI. Despite consistent support from the literature on best practices for prevention, recognition, and treatment of EHI, negative outcomes still occur. Reasons why high school ATs fail to implement and execute evidence based protocols may be explained through use of the Social Cognitive Theory (SCT). To date, no current research takes a theoretical approach when exploring an AT’s prevention, recognition, and treatment of EHI. Therefore, the purpose of this study was to describe ATs’ utilizations of best practice guidelines for prevention, recognition, and treatment of EHI in high school athletes relative to constructs of the SCT. A secondary purpose was to provide a foundation for the development of theory-based education programs for ATs to evoke long-term behavioral changes towards compliance with EHI guidelines. This information provides a foundation for the development of theory-based education programs for ATs to evoke long-term behavioral changes towards compliance with EHI guidelines. The most common barrier to having a set heat acclimatization plan selected was “other” which included the use of basic “state guidelines” or state regulations preventing individual plans. The most common barrier to the utilization of rectal temperature was invasiveness/privacy, and the most common barrier to the utilization of CWI was limited resources/staff. Findings of this study indicate that barriers to the use of rectal temperature and CWI are based on individual factors as opposed to circumstances outside of their control. This concludes that intervention strategies may need to be implemented on the individual level as opposed to the institutional level. It is also noted that questions relating to all constructs of the SCT had a significant relationship with the utilization of rectal temperature. The long-term goal of this line of research is to increase ATs’ utilization of best practice guidelines regarding EHI which could prevent heat-related illness and death in the patients that they treat.