Despite evidence that annual mammographic screening in women 50 years and older reduces mortality, surveys of physicians and patients have repeatedly demonstrated that annual screening mammography is not performed. The fundamental question addressed in this chapter is: If the assumption is made that the scientific evidence supports the use of mammography, what, then, are physician-related barriers to mammographic screening of elderly women? Using a model that classifies barriers to implementing prevention protocols into three categories (predisposing, enabling, and reinforcing factors), literature is reviewed to help identify reasons for low mammographic screening rates, especially in elderly women. This article concludes with a discussion of strategies that may help overcome barriers to mammographic screening in elderly women.