This two-part issue of the Endocrinology and Metabolism Clinics of North America brings the practicing endocrinologist up to date on the most important topics in pediatric endocrinology. Part I covers genomics: genetic disorders and new techniques; newborn screening; hormones in the premature infant; congenital disorders of the thyroid: hyper/hypo; glucose in the PIC setting; diabetes prevention; obesity: etiology, prevention, and treatment; metabolic syndrome in pediatrics; complementary and alternative medicine in pediatric endocrinology; imaging in pediatric endocrine dosoirders; U/S gonads; and global epidemiology of Type 1 diabetes.