The recent surge of interest in astrobiology has led to a spate of books in astrobiology — combining astronomy and biology — but in most of these, cometary panspermia is dealt with only cursorily. The present book sets out the case for cometary panspermia in a cogent way, combining evidence from space science, celestial mechanics, geology and microbiology. It should be an essential part of any university course on astrobiology, and also serve as a reference textbook for researchers in the field.