Background: Self and close other reports of communication ability can provide a time-efficient means of evaluating conversational discourse after traumatic brain injury (TBI). The La Trobe Communication Questionnaire (LCQ) measures perceived communication ability from various sources including self-perceptions and perceptions of others. Content and test-retest reliability and discriminant validity of the LCQ have been demonstrated previously with adults following TBI. Aims: This study was undertaken to explore the factor structure of the LCQ as revealed within the data collected from 88 adults with severe TBI and their close others. Methods & Procedures: Construct validity was examined using a Principal Component Factor Analytic procedure with Varimax rotation. Outcomes & Results: A seven-factor structure that accounted for 60.88% of the variance was revealed. Of the LCQ items, 27 clearly loaded on to one of the seven communication factors that were identified. Conclusions: The factor structure that emerged depicts the multidimensional nature of conversation and the complex interplay between cognitive and communication processes that social discourse demands. These results support the construct validity of the LCQ and indicate that it can be used as a reliable and valid measure of communication ability after severe TBI.