This preliminary, pilot study assessed the effectiveness of a group-based, mindfulness intervention in a residential, rehabilitation setting with specific focus on assessing participants' self-report of perceived benefit of the intervention on overall health, pain, sleep, mood/anxiety, attention, and self-awareness, as well as implementing modifications needed for successful intervention application among a diverse, clinical military population. Participants were 19 veterans and active duty service members with a history of traumatic brain injury (TBI; 63% severe) who completed a mindfulness-based group intervention during inpatient admission at a Veterans Affairs Polytrauma Transitional Rehabilitation Program (PTRP). Mindfulness and yoga skills were taught in a required, weekly group incorporated into participants' rehabilitation schedule. Opinions and attitudes about mindfulness, as well as pertinent self-report outcome measures, were obtained pre- and postgroup participation. Results suggested that participation in the group was positively associated with individuals' self-reported belief about the benefit of mindfulness in the areas of overall health, physical health, mood, focus, and self-awareness. The more groups attended, the more positive the participants' beliefs about potential impact on overall health and mood became, even while controlling for length of rehabilitation stay. Additionally, several specific group modifications relevant to this population (e.g., physical/environmental modifications, repetition, ignoring/reorienting) were implemented to support successful participation. These preliminary and exploratory findings suggest that it may be worthwhile for psychologists, clinicians, and other health care providers working with a mixed TBI population, and more specifically a military population with TBI, to consider introducing mindfulness skills as part of multidisciplinary rehabilitation. (PsycINFO Database Record