Nitric oxide (NO) is a key regulator of various cellular signaling pathways throughout the body and plays an important role in renal function under normal physiological and pathophysiological conditions. NO plays a major role in the regulation of renal hemodynamics, tubuloglomerular feedback, sodium transport in the nephron, pressure natriuresis, and renal fibrosis and injury; moreover, a deficiency in NO is characteristic of chronic kidney disease in both human patients and in experimental animal models. The goal of this book is to highlight the actions of NO within the kidney and its effects on the regulation of renal blood flow and tubular transport.