The 4th edition of Understanding Paediatric Anaesthesia was undertaken due to its popularity among students and requests from many of them to update the book while keeping it succinct and simple. The authors and editors have tried to keep it as such. This is, therefore, a simple yet comprehensive text that presents a practical approach to anaesthetizing children, neonates and infants both for elective cases and in the emergency setting. Its simplicity is directed at the young student of anaesthesia, the occasional paediatric anaesthetist and those working in rural areas who do not have the time or need to read more complex books on paediatric anaesthesia.