PROJECT SUMMARY/ABSTRACT Recommendation for treatment of hearing loss with hearing aids is usually driven by results of tests of auditory thresholds, middle ear function, and word recognition, which provide the audiologist with an accurate picture of peripheral and central auditory system function. However, only an estimated 20- 30% of individuals identified as hearing-aid candidates, report using them 1. Hearing handicap, which is only moderately correlated with hearing loss, is a better predictor of who may need and benefit from hearing aids 2, 3. However, the factors that contribute to self-reported hearing handicap are not well understood. Research regarding hearing loss treatment is primarily focused on hearing-related (e.g., elevated thresholds, reduced speech-in-noise perception) or device-related (e.g., compression strategies, noise reduction technology) factors, with fewer studies, focused on the effects of individual differences in psychological factors, such as personality and cognitive abilities. The current study proposes to use advanced statistical techniques to investigate how individual differences in personality and cognition contribute to and define the construct of hearing handicap, and determine how hearing loss, hearing handicap, cognition, and personality influence hearing aid use. Results from this program of research will inform the development of more comprehensive and effective hearing healthcare treatment options for the growing number of older adults with hearing handicap across the United States.