The purpose of this study was to explore the impact of Medicaid on changes in coverage among women with newly diagnosed breast cancers, in the first years of program implementation. Women and their providers used the program, with nearly double the number of women covered by Medicaid in the three years after implementation. The treatment program, as implemented in Oklahoma, reached the target population and provided coverage to women who previously had none. The study found a promising, though nonsignificant, reduction in the time between diagnosis and treatment among women diagnosed with breast cancer when Medicaid was their primary payer.