Introduction: Current Aims and Center Theme. This proposal is for renewal of the UlC-Center for Population Health and Health Disparities (P50 CAI 0674). This Center is one of five that were funded in whole or in part by the National Cancer Institute as part of the initial NIH initiative. It is a Multiple Principal Investigator application. The center theme is: Understanding how our previous research identifying fundamental causes of disparities in stage at breast cancer diagnosis related to race/ethnicity can lead to interventions grounded in that research? The current aims of the proposed renewal of the Center are to address three questions that have emerged as central issues in understanding the disparity in stage at breast cancer diagnosis between White women and women of color based on our work to date. These are: I) To define how apparent disparities in early detection, diagnosis and treatment can be addressed in safety-net hospitals? 2a) Determine how community health clinics can more effectively identify and monitor patients at risk for aggressive breast cancer. 2b) Determine how patients at elevated risk can be engaged to participate in a tailored screening and monitoring program. 3) To determine how biological factors, specifically DNA methylation, promote aggressive breast cancer disproportionately among women of color? . There are three projects: .1) Patient Navigation in Medically Underserved Areas. (E. Calhoun, PI) 2) A Breast Cancer Screening Intervention to Improve Adherence to Cancer Control Guidelines in Underserved Minority Women (K. Hoskins, PI); DNA Methylation and Differential Cancer Aggressiveness by Race/Ethnicity (G. Rauscher, PI) and four cores: Administration (R. Warnecke (Contact) & E. Calhoun (Co- Core leaders); Policy and Dissemination (C. Ferrans, CL); Data Management and Evaluation (T. Johnson, (CL) and Training and Career Development (F Davis, CL ) Our continuing, long range vision is to test and establish interventions that address determinants of population health disparities by approaching them with a multilevel and multidisciplinary population health strategy. To accomplish this we will: 1) conduct research that impacts the policies that govern access to mammography and management of breast cancer and ensures equal access to the standard of breast cancer care regardless of where it is delivered and who requests it. 2) Enable women who are poor and underserved to recognize the need to access the care in ways that ensure the best outcomes. 3) To train young scholars in health disparities research incorporating a transdisciplinary research perspective.