Objective: The impact of breast cancer is immense for all women, but the literature reveals an even greater impact on women of color and among socially and economically disadvantaged populations. Persistent differences in incidence and outcome are undoubtedly due to multiple factors, but one element in poor outcome may be treatment choice. Those treatments shown to be related to best outcomes are less likely to be chosen by certain groups of women. The effects of economic and cultural factors on breast cancer treatment choice have not been thoroughly explored; these factors must be understood if health care professionals are to intervene effectively to address disparities and improve breast cancer outcomes for all women. Methods: A review of the breast cancer literature was conducted in order to: (1) describe breast cancer disparities in the United States; (2) delineate factors that might contribute to those disparities; (3) assess possible mitigating factors for predominant causes; (4) begin to decide how health care interventions might allay the factors that contribute to disparities in breast cancer incidence and mortality. Results: Breast cancer incidence and outcome disparities in the United States are due to multiple interacting factors. These include information about treatment, different types of treatment, the emotional context of decision-making, and patient preference for level of involvement. Treatment decision-making is complex. Conclusion: Health literacy and level of decision-making involvement, both embedded in social and economic reality, are key components in breast cancer treatment decision-making and may contribute to breast cancer disparities in the United States. Current models of shared decision-making may not be generalizable to all breast cancer patients. Practice implications: Optimal breast cancer outcomes for all women depend on culturally and ethnically appropriate professional support. #