Chronic kidney disease (CKD) is a major public health problem in the United States that affects 37 million Americans and disproportionately burdens racial and ethnic minority populations. Advances in personalized medicine approaches for patients with CKD lag behind advances in other fields. Current approaches to classifying CKD do not provide granular insight into the underlying mechanisms that contribute to the heterogeneity of the disease. To address this gap, NIDDK established the Kidney Precision Medicine Project (KPMP) in 2016 with the overarching goal of using deep molecular phenotypes of kidney biopsies, along with longitudinal clinical phenotypic data to develop new disease ontologies and treatments for kidney disease. This proposal for a University of Illinois at Chicago (UIC) KPMP CKD Recruitment Site brings together a diverse multidisciplinary team of experienced investigators with expertise in nephrology, renal pathology, interventional radiology, bioethics, social determinants of health, and biostatistics. Our team has a successful track record in recruiting and retaining large and diverse populations of patients with CKD in long-term studies. This proposal has three overarching goals: 1) Utilize our well-established and successful recruitment strategies to enroll 100 participants (50% non-Hispanic Black, 30% Hispanic) from the University of Illinois Health Science System and a large affiliated federally qualified health center to undergo high-quality research kidney biopsies, conforming to the highest ethical, research and clinical standards; 2) Leverage the infrastructure of the UIC Chronic Renal Insufficiency Cohort (CRIC) Study Clinical Center to enroll 50 eligible CRIC participants into KPMP, providing an unprecedented opportunity to link data from this deeply phenotyped cohort with KPMP kidney biopsy measures; and 3) Implement a systematic assessment of neighborhood-level measures of social determinants of health which will advance the overall mission of KPMP to better characterize disease subgroups. We will use an established real-time electronic health record-based reporting system to identify eligible individuals in the two health care systems and then engage potential participants in an open discussion of the risks and benefits of a research kidney biopsy. Additionally, we will utilize patient-centered strategies to maintain long- term patient engagement and achieve high rates of retention with the guidance of a local Community Advisory Board composed of key stakeholders (i.e., patients, a caretaker, and a primary care provider). Leveraging our expertise and experience working with NIDDK U01 cooperative projects, we will rapidly and effectively implement the KPMP protocol, work collaboratively with the consortium, and will make substantial contributions to the long-term scientific mission of KPMP to develop precision medicine-based approaches for treating kidney disease.