During the years that she has been working in Paediatric Allergology, Dr Kefala has been confronted from the very beginning with questions from allergic children and their parents regarding the origin of their allergic diseases and what these imply in their lives and the lives of their families. Adequate and complete awareness of allergic children and their families about allergies is essential to gain the confidence of the young patients and the full cooperation of their families in the treatment of their allergies. In this book, Dr Kefala describes the course of allergies in allergic children by starting with the original question : How do allergies develop? She discusses in simple words the genetic, environmental and epigenetic factors which play a role in the occurrence of allergies. Dr Kefala explains the tests used to diagnose allergies, the allergy treatments and secondary and tertiary prevention of allergic diseases. One of the most common food allergies in children is egg allergy. For these reasons, Dr Kefala has added an explanatory sheet for egg allergy. It helps moderately severe allergic children to deepen their investigation and to limit and outgrow their allergy.