Chronic kidney disease (CKD) affects approximately 26 million Americans and disproportionately manifests in specific race and ethnic groups. Patients burdened with CKD have significant morbidity and reduced life expectancy. In addition to excessive suffering and lost productivity, the cost of managing this epidemic has reached $40 billion annually. The recognition that CKD is a major public health problem is reflected in the fourteen objectives outlined in Healthy People 2020 to begin to address the disease burden. Advancement in approaches to halt CKD progression has been slow despite growing global awareness of disease burden. This O'Brien Kidney Research Core will create opportunities for novel insights through characterization of tissue profiles that will define new disease markers and molecular pathways and will be available to all kidney investigators on the www. It will thereby fundamentally alter the starting point for research into prevention of progression of these kidney diseases. C-PROBE is an essential element of the center grant and presents a biomedical resource core consisting of: (1) clinical phenotyping (that is, systematic identification of observable physical and biomedical characteristics) of kidney disease patients including the accurate measurement of kidney function; and (2) a specimen BioBank which will store blood, urine and kidney tissue samples. A key component of C-PROBE is therefore that it contains a proven mechanism to collect samples from high risk groups including minorities, at the institutions of University of Michigan Health System, St. John Hospital, Wayne State University in Michigan, John H. Stroger Hospital in Illinois, Temple University Health System in Pennsylvania, and Levine Children's Hospital in North Carolina. This mechanism will feed the other Cores and provide biomedical investigators with approved projects the access to a dynamic pool of well characterized high risk kidney disease patients and their biological specimens to conduct high caliber translational research.