Impaired awareness of the effects of brain injury is a commonly observed and poorly understood finding in traumatic brain injury survivors. Nonetheless, impaired awareness has been identified as a major factor in determining outcome for traumatic brain injury survivors. Review of previous studies of impaired awareness in this patient population revealed a number of preliminary findings regarding the nature of this phenomenon. The present paper presents the results of 2 new studies with a total of 111 traumatic brain injury patients conducted to bring further clarity to this area. Findings confirmed and extended many results of previous investigations. Specific findings included patient overestimation of functioning as compared to family member ratings, patient report of greater physical than nonphysical impairment, greater patient–family agreement on specific ratings of patient functioning than on general ratings, greater agreement of family and clinician ratings of patient functioning with each other than with patient self-ratings, and partial disagreement of different methods of measuring impaired awareness. (JINS, 1998, 4, 380–387.)