Molecular Toxinology has been established as a scientific discipline focused on the interconnected description of various aspects of animal toxins, which appear as an invaluable source for the discovery of therapeutic polypeptides in an investigative biotechnological world. Animal toxins rely on particular chemical interactions with their partner molecule to exercise their biological actions. The comprehension of how molecules interact and identify their target is important for the rational exploration of bioactive polypeptides as therapeutics. Investigation on the mechanism of molecular interaction and identification provides a world of new opportunities for the pharmaceutical industry and clinical medicine. This book presents topics on molecular cloning and genetics, and molecular recognition.