ABSTRACT A significant challenge in the empirical study and clinical management of cognitive-communication impairment, a hallmark deficit in individuals with traumatic brain injury (TBI) and Alzheimer's disease (AD), is that commonly used methods to detect these deficits in clinical and research settings lack the required sensitivity and have focused on a limited subset of discourse tasks that do not reliably predict communication outcomes. At the heart of our proposal is the idea that current theories of cognitive-communication are too narrow and the methods used to detect deficits are too limiting. In contrast to current conceptualizations which state that cognitive-communication deficits affect discourse and conversation (leaving basic sentence level processing intact), we propose that cognitive-communication impairment is a deficit in the flexible use and processing of language that manifests across the varied and dynamic contexts of everyday language use, whether processing a single sentence or participating in a multiparty conversation. From this perspective, there is a striking disconnect in the field between clinical observations of impairments in using language in context and the widespread use of decontextualized tasks and measures to capture these deficits in the lab and clinic (e.g., monologue discourse task). Using ecologically valid language tasks and methods sensitive enough to detect even subtle, though meaningful, disruptions in language, this administrative supplement extends our work on language processing in TBI to individuals with Alzheimer's disease. The proposed program of research represents a novel direction in the study of cognitive communication impairment in individuals with AD with substantial basic science and clinical translational significance. The proposal is organized around two AIMS: (1) To investigate language processing in context in AD; (2) To investigate language use in group settings in AD. This proposal is unique in the field and uniquely promising for understanding the nature of deficits in contextual language processing and, ultimately, improving rehabilitation intervention outcomes.