In collaboration with Consulting Editor, Dr. Lucky Jain, Drs. Robert Kliegman and Bret Bordini  have put together topics that provide a current clinical update on the treatment and management of undiagnosed and rare diseases in the neonate.  Expert authors have contributed clinical review articles on the following topics:  Neonatal Liver Failure; Neonatal Autoinflammatory Disorders; Rare or Unusual Dermatologic Disorders In Neonates; Neonatal Immune Deficiency; Congenital Diarrhea Syndromes; Nonimmune Hydrops; DNA Depletion Syndromes; Genomic Approach to Dysmorphology Syndromes; Nonimmune Anemias; Severe Metabolic Crisis (Metabolic Acidosis, Unresponsive Hypoglycemia, Hyperammonemia); Heterotaxia Syndromes; Neonatal Appendicitis; Avoiding Diagnostic Errors in Neonatology; and Differentiating Congenital Myopathy from Congenital Muscular Dystrophy.  Readers will come away with the information they need to improve outcomes in the neonate.