The care of the newborn has become a team sport; one where teamwork is crucial. We can no longer think exclusively of the neonatology healthcare team, but must also consider all of the other sub-specialty disciplines. While some of these disciplines are not always available at all healthcare facilities, generally radiology is. This is because one of the first investigations performed on so many ill newborn infants is the straight x-ray. This alone makes it imperative that the neonatal team and the radiological team speak the same language. This is one of the main purposes of this book: to allow juniors in each discipline an introduction to what the other player is thinking of as regards presentations, differential diagnoses, etc. Both medical specialists (i.e. neonatal, renal, and obstetric disciplines) and radiologists have combined to outline how this dialogue takes place for an individual infant. We intend here to illustrate a joint approach to the ill infant. Nowadays the learning demands on junior strata of the entire healthcare multidisciplinary team that gets involved in looking after an ill infant are enormous. Unsurprisingly, the needed emphasis on any single aspect of the clinical assessment may not be always possible. This is true of the radiological assessment. By selective examples, we hope that learners who feel the need for a fuller immersion in this discipline will find this book of benefit. Hence this is the second main purpose of this book.