This proposal requests support for the continuation of a research training program in academic nephrology, under the directorship of Dr. Martin Pollak, Chief, Nephrology Division, Beth Israel Deaconess Medical Center (BIDMC) and Professor of Medicine, Harvard Medical School (HMS). Support is requested for five trainees who will typically spend at least two years in the training program. As in the past, we expect that most candidates will have received the MD degree or the MD-PhD degree prior to entry but prospective trainees with a PhD and a background in a relevant scientific discipline are also considered. The major criterion for selection is evidence of an interest, ability and commitment for a career in investigative nephrology. Research activities span basic and translational investigations. Current research areas include acute renal failure, mechanisms of cell injury and cell metabolism, ion transport and water excretion, cellular transduction mechanisms, preeclampsia, glomerular pathology, genetics of kidney disease, cellular and transplant immunology, gene regulation, genomics and proteomics of the kidney, angiogenesis, vascular leak, diabetic nephropathy, metabolism, and epidemiology. The chief method of instruction is intensive personal involvement in a research program under the close supervision of an experienced mentor. Participation in a structured program of career mentoring, research seminars, journal clubs, and laboratory presentations is mandatory for all trainees. The primary facility for training is the Nephrology Division at BIDMC, with additional training sites in the Transplant, Rheumatology, and Cardiology Divisions at Children's Hospital Boston, the Dept. of Medicine (Renal Division) at Brigham and Women's Hospital, the Wyss Institute, the Broad Institute, and the Renal Unit at Massachusetts General Hospital. A variety of core facilities (animal, genetics, imaging, biochemical, etc.) are available at BIDMC and/or Harvard Medical School, the Harvard CTSA, and at the other training sites. These sites are close to each other, facilitating interactions.