PROJECT SUMMARY/ABSTRACT Since 2002, the NIDDK has sponsored four phases of the prospective Chronic Renal Insufficiency Cohort (CRIC) Study, which enrolled a combined cohort of >5400 adults with chronic kidney disease (CKD) at seven Clinical Centers across the U.S. to address the overarching goals of identifying risk factors for CKD progression and clarifying the relationship between kidney dysfunction and the risks of subclinical and clinical cardiovascular events, death, resource utilization and other patient-centered outcomes. The most recent Phase 4 (ending June 2023) has further innovated on remote data collection methods and more granular investigation of kidney function trajectories and cardiovascular sub-phenotypes across the spectrum of CKD severity. The proposed CRIC Phase 5 will leverage the cumulative experience, expertise and success of the CRIC Study network by creating mechanisms for future data collection and analyses and generating tools and resources for ongoing use of the extensive longitudinal CRIC data and biospecimens. CRIC Phase 5 will strengthen the existing unparalleled resource for the broader research community that will enhance the science related to CKD to achieve the ultimate goal of improving clinical and patient-centered outcomes. The Kaiser Permanente Northern California/University of California, San Francisco (KPNC/UCSF) Clinical Center has been a leader within the CRIC Study and the Specific Aims to be addressed in CRIC Phase 5 by the KPNC/UCSF Clinical Center are: 1. To complete clinical outcome ascertainment for the CRIC participants enrolled in the sub-protocols initiated during Phase 4, including in-home testing of kidney function and damage and ambulatory measures of cardiac arrhythmias and cardiovascular reserve 2. To complete follow-up of eligible CRIC participants 3. To conduct analyses that integrate the data collected through the Phase 4 sub-protocols with previously collected data and outcomes to identify novel risk factors and sub-phenotypes for CKD progression, cardiovascular and other outcomes 4. To facilitate linkages with external data sources to allow acquisition of additional data for future investigations 5. To transfer data and collect and ship biological specimens to the CRIC Scientific and Data Coordinating Center for transfer to NIDDK Central Repository to support future research 6. To promote dissemination of tools to facilitate the use of CRIC resources by investigators in the broader scientific community during and beyond the end of the CRIC Study