Nephrology deals with the study of the function and diseases of the kidney. Autosomal Dominant Polycystic Kidney Disease (ADPKD) is the cause of renal failure in 5-10% of the patients in dialysis or transplantation. This book discusses the several conditions which are associated with the rate of progression. Peritoneal dialysis (PD), which has been widely used as one of the major renal replacement therapies for end-stage renal disease (ESRD) patients is also explored in this book. Furthermore, the important role of PAI-1 and the value of therapeutic approaches targeting PAI-1 in progressive renal fibrosis is also examined. Because renal interstitial fibrosis occurs in virtually all the progressive renal diseases leading to end-stage renal failure, controlling it would be a reasonable therapeutic strategy. Other chapters in this book include a review of therapeutic plasma exchanges (TPE), the potential mechanisms that may regulate the effect of macrophages upon renal interstitial fibrosis and the pathophysiological implications of inflammation in the pathogenesis of diabetic nephropathy.