Knowledge is an important component of cognitive functioning and its role is becoming increasingly acknowledged in theoretical work on cognition and intelligence. Because knowledge stores increase with age, researchers have questioned whether the benefits of knowledge can outweigh age-related declines typically found in the mechanics of processing. Some data suggest that the acquisition and the use of knowledge require some effort and therefore could benefit from increased levels of perceived control. Yet it remains unclear how knowledge and control beliefs jointly affect cognitive processing and whether there are age differences in these processes. In light of the research indicating that control beliefs are particularly important among older adults, control beliefs may be an important antecedent of knowledge use among older adults. Three encoding processes that have been identified as possible mediators of the relationship between control beliefs and cognitive performance are persistence, strategy use, and task engagement. The proposed research investigates a mediational model in which the relationships among age, control beliefs, knowledge and memory performance are explored and the mediational role of these encoding processes are considered. The long-term goal of this research is to better understand how knowledge and control beliefs can offset age-related declines in cognitive processing.