Chronic kidney disease (CKD) involves a fixed deficit or progressive deterioration in kidney function, producing variable losses of normal physiologic functions. In adolescents, CKD results from a wide range of causes. Because of the broad spectrum of disease, the physician providing primary care to the adolescent must be knowledgeable about findings leading to the diagnosis of CKD and must understand the physiologic basis for therapeutic management. Complications of normal renal function loss include issues of fluid, electrolyte, and acid-base balance, as well as development of anemia, cardiovascular disease, metabolic bone disease, and growth failure. Goals of therapy include anticipation and replacement of lost physiologic functions so that the adolescent can grow and develop normally.