To develop and evaluate a model of environmental factors-participation relationships for persons with traumatic brain injury (TBI), stroke, and spinal cord injury (SCI), and test whether this model differed across three diagnostic groups, as well as other demographic and clinical characteristics.A cross-sectional observational study included 545 community-dwelling adults with neurological disorders (TBI = 166; stroke = 189; SCI = 190) recruited at three academic medical centers. Participants completed patient-reported measures of environmental factors and participation.The final structural equation model had acceptable fit to the data (CFI = 0.923; TLI = 0.898; RMSEA = 0.085; SRMR = 0.053), explaining 63% of the variance in participation in social roles and activities. Systems, services, and policies had an indirect influence on participation and this relation was mediated by social attitudes and the built and natural environment. Access to information and technology was associated with the built and natural environment which in turn influence on participation (ps < 0.001). The model was consistent across sex, diagnosis, severity/type of injury, education, race, age, marital status, years since injury, wheelchairs use, insurance coverage, personal or household income, and crystallized cognition.Social and physical environments appear to mediate the influence of systems, services, and policies on participation after acquired neurological disorders. These relations are stable across three diagnostic groups and many personal and clinical factors. Our findings inform health and disability policy, and provide guidance for implementing the initiatives in Healthy People 2020 in particular for people with acquired neurological disorders.