Breast cancer incidence increases with age, but many older women do not receive appropriate mammography screening. A tool to support provider decision making holds potential to help providers and patients reach the best-informed decisions possible. We developed and tested a decision aid (DA) for healthcare providers to use in mammography screening recommendations in older women. Literature review, expert opinion, focus groups, and pilot testing of the DA were conducted in a university ambulatory geriatrics practice. Provider evaluations of the DA after piloting were collected and analyzed. Geriatricians reported important factors in decision making included patient life-expectancy, preferences, cognitive function, and individualization. Geriatricians reported the DA would have helped them make recommendations for mammography screening in 66% of pilot cases. It was less helpful when there was more certainty regarding decision making.