Background: A requisite skill for successful conversation is the ability to adjust one's language according to contextual factors. Aims: This study examined one aspect of language use in context--the use of mental-state terms, i.e. words that communicate thoughts, beliefs or feelings--in conversations between adult males with and without traumatic brain injury (TBI) and familiar partners. Methods & Procedures: Participants were five males in the chronic stage of recovery following severe TBI and five male peers matched for age, conversing with friends. Conversational context was manipulated using conversation starters that were designed to induce differing levels of self-disclosure or intimacy, with the expectation that mental-state term use would increase when participants talked about more intimate topics. Outcomes & Results: Participants in both groups used more mental-state terms in more intimate conversations; however, adults with TBI did not increase their mental-state term use to the same extent as matched peers. Adults with TBI also used a significantly different pattern of mental-state term types across intimacy levels as compared with peers. Conclusions & Implications: These quantitative and qualitative differences may contribute to social conversation problems of adults with TBI. (Contains 3 tables and 3 figures.)