Military service members (SMs) are surviving complex battlefield injuries at higher rates than ever before. Cutting-edge technologies are increasingly being employed to improve assessment and treatment of these complex injuries. The Computer Assisted Rehabilitation Environment (CAREN) is a comprehensive immersive environment, featuring a treadmill, curved panoramic screen, audio array, and infrared cameras to capture movement. While the CAREN has been progressively incorporated in treatment and research, little has been reported regarding participants' subjective experiences, particularly in relation to the signature wounds of the Iraq and Afghanistan wars, traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD). Here we report participant presence, in a cohort of SMs with complex, frequently dual-diagnosis injuries (N=148; 95% TBI; 58% PTSD) engaging in CAREN-driven treatment. Using a presence questionnaire, participants rated aspects of the CAREN on a 7-point Likert scale and a presence score was calculated. The average presence score was 46.83 (SD=6.04; possible score range 7-63), with 95% of participants reporting scores >36. Those with motion sickness and eye discomfort reported lower presence, whereas those with PTSD reported higher presence. Presence did not vary according to TBI severity. Overall, SMs with complex injuries experience presence in the CAREN. However, presence may be adversely affected by CAREN-associated symptoms such as motion sickness.