This article reports an investigation into the cognitive and linguistic mechanisms involved in knowledge management during discourse production of persons with AD. Two discourse variables were examined, incomplete propositions and repeated propositions. Differences between controls and participants with AD were found concerning the presence of incomplete propositions in a non informative prompted task. Findings obtained with the informative prompted task suggested that knowledge management was more preserved in the early stage than in the later stage of AD. The majority of the neuropsychological data correlated with the presence of incomplete propositions. The discussion debated whether this discourse deficit can be attributed to an impairment of the ability to manage knowledge provided in the context of communication.