PROJECT SUMMARY With an increasing aging population showing memory declines, many of which remain untreatable, finding ways to reduce prospective memory failures is critical for healthy aging. Prospective memory is necessary for maintaining independence with increased age and failures of prospective memory are associated with a variety of health consequences and difficulties in daily activities. For example, over 55% of older adults do not adhere to medication instructions, leading to the annual hospitalization of over 200,000 older adults due to adverse drug reactions and billions of dollars annually in avoidable direct healthcare costs. Offloading information onto external sources, such as setting an alarm to take medication, provides an easy and effective means to mitigate age- related prospective memory declines. However, a lack of basic knowledge about the cognitive and metacognitive processes underlying offloading decisions presents barriers to effective implementation. The purpose of this proposal is to address these gaps in knowledge by examining the role of offloading during prospective memory encoding, storage, and retrieval. This will be accomplished by combining behavioral and physiological (pupillary) measures to examine how and when age-related breakdowns in prospective memory occur (Aim 1) and examining how strategy training can be used to ameliorate age declines in remembering (Aim 2). The results will provide a comprehensive theoretical framework for identifying the mechanisms underlying prospective memory, the source of age-related declines in prospective memory, and the efficacy of cognitive and strategy training as a memory enhancement technique. The long-term goal of this research is to develop the capacity to identify who will benefit most from strategy training interventions and which specific strategies should be targeted. Individually tailored treatment options will result in increased ability to improve cognitive functioning for those experiencing age-related memory decline. This work is innovative in its novel use of pupillometry to examine cognitive processes not otherwise observable with standard behavioral measures and through the development of an online training tool to improve everyday prospective memory. The findings will be significant for understanding treatment options to improve prospective memory functioning in younger adults, older adults, and individuals with Alzheimer’s disease and related dementias.