The purpose of the present study was to investigate the relationship between patients' compliance and awareness and outcome of brain injury rehabilitation. Subjects were 98 patients who underwent a holistic neuropsychological outpatient rehabilitation programme. Patients had suffered a traumatic brain injury (n = 26), a cerebrovascular accident (n = 58), or another neurological insult (n = 14). Measures: Two staff members, a neuropsychologist and a physiotherapist, retrospectively and separately rated patients' awareness and their compliance. Outcome was measured with the d2 test of concentration, measures of oxygen uptake, strength endurance, running speed, and patients' and relatives' ratings of patients' cognitive, physical, and overall problems on the European Brain Injury Questionnaire (EBIQ). The discrepancy between patients' and relatives' ratings on the EBIQ was incorporated as a second measure of patients' awareness. Results: The neuropsychologist's compliance ratings were significantly related to measures of insight, improvement of d2 performance accuracy and stability, improvement of oxygen uptake, and reduction of cognitive and overall problems as reported by the patients, while the physiotherapist's compliance ratings were related to measures of insight, improvement of d2 performance speed, improvement of oxygen uptake and strength endurance, and all three EBIQ patient scales. Discussion: The results suggest a differential relationship between situation-specific compliance and outcome.