This research assessed the impact that physical inaccessibility of provider locations has on the substance abuse treatment participation of two groups of persons with disabilities. A random sample of treatment providers in the Mid-Atlantic region were surveyed and asked if they had declined services to persons with spinal cord (SCI) or traumatic brain (TBI) injuries due to the inaccessibility of their practices. Over half of those who had been approached by persons with SCI and nearly half of those approached by persons with TBI were unable to provide services due to physical barriers. The inability to serve such individuals was not related to practice affiliation (public or private) or practice type (hospital based, non-medical residential, or outpatient). These findings support earlier research indicating the treatment participation of persons with disabilities is negatively affected by physical accessibility concerns.