Collecting and reporting data on race and ethnicity is vital to understanding and addressing health disparities in the United States. These health disparities can include increased prevalence and severity of disease, poorer health outcomes, decreased access to healthcare, etc., in disadvantaged populations compared with advantaged groups. Without these data, researchers, administrators, public health practitioners, and policymakers are unable to identify the need for targeted interventions and assistance. When researching or reporting on race and ethnicity, typically broad racial categories are used. These include White or Caucasian, Black or African American, Asian American, Native Hawaiian or Other Pacific Islander, or American Indian and Alaska Native, as well as categories for ethnicity such as Latino or Hispanic or not Latino or Hispanic. These categories, defined by the Office of Management and Budget, are the minimum standards for collecting and reporting race and ethnicity data across federal agencies. Of note, these categories have not been updated since 1997. The lack of accurate and comprehensive data on marginalized racial and ethnic groups limits our understanding of and ability to address health disparities. This has implications for breast cancer outcomes in various populations in this country. In this paper, we examine the impact data inequity and the lack of data equity centered processes have in providing appropriate prevention and intervention efforts and resource allocations.© 2023. Society of Surgical Oncology.