 A blind randomized study of celecoxib in women at high risk of developing breast cancer. Subjects are to take twelve months of drugplacebo. At baseline and after twelve months subjects will have a random periareolar fine needle breast aspiration that will be assessed for epithelial cell growth and other markers of risk. Baseline and twelve month serum samples will also be assessed for hormones and growth factors which may be associated with breast cancer risk. Mammograms at baseline and twelve months will also be assessed for breast density changes. 