Lessons in Immunity: From Single-cell Organisms to Mammals stems from the activity of the Italian Association of Developmental and Comparative Immunobiology (IADCI), represented by the editors. This book is presented as a series of short overviews that report on the current state of various relevant fields of immunobiology from an evolutionary perspective. The overviews are written by authors directly involved in the research, and most are members of the IADCI or have otherwise been involved in the related research for their respective overview. This publication offers scientists and teachers an easy and updated reference tool.