The DSHS Traumatic Brain Injury Task Force was formed to ensure that Department clients who suffer traumatic brain injuries receive adequate and appropriate services. Traumatic brain injuries are insults to the brain caused by an external physical force, anoxia, or traumatic encephalopathy. Traumatic brain injured persons suffer long term impairment of their state of consciousness and/or cognitive, physical, behavioral, or emotional functioning as a result of such injuries. The Residential and Related Services Work Group was charged with the responsibility of drafting a report describing the current service delivery system for persons with traumatic brain injuries (TBI). This companion report estimates the incidence of TBI in Washington in 1985 and 1986, and provides some demographic information about acute care patients with TBI. Using ICD-9 CM codes, TBI incidence data were extracted from the Commission hospital Abstract Reporting System (CHARS) maintained by the Washington State Hospital Commission. The CHARS extract files were unduplicated to convert discharge records to individual patient records. The findings in this summary are based on CHARS extract files for 1985 and 1986.