This article describes the Head Injury Family Interview (HI-FI), a five-part structured interview designed to gather clinical and research data on persons with head injury and their family members. The HI-FI was developed over a 10-year period at the Research and Training Center on Head Injury and Stroke of New York University Medical Center to track outcomes of persons recovering from traumatic brain injury, with input from both the injured person and significant others, and to document the impact of the injury on the family system. The structure, contents, rationale, and development of the interviews are described, as well as its clinical utility and research potential. In addition, the statistical properties of one particular instrument within the interview, the Problem Checklist, are detailed and data presented from a multicenter study.