The purpose of this book is to fill the gap in a largely neglected fundamental branch of biology and medicine that is now becoming a hot topic. Although interest in the excellent protective power of hereditary immunity was sporadically characteristic of the history of immunology, its investigation has been out of the main stream of the science. Its origin and the mode of action have been beyond comprehension and exploitation. The agnostic attitude began to change very dramatically only at the edge of XXl Century. Until now, there has been no review book on the entire topic of hereditary immunity published in English. This is the first in-depth analysis of hereditary immunity both in the investigation of life and in health care.