The book presents a defense of Classical theory of criminology which is now largely marginalized. The Classical approach remains relevant for the contemporary problems of criminal justice. A reader will find a critical examination of different schools of criminology as well as criminological initiatives within various national systems of criminal law. Classical criminology stands closer to a theory of criminal law, and particularly comparative criminal law, than any other criminological theory. It emphasizes the importance of free will and moral responsibility of offenders. Classical criminology is humanistic. It affirms the dignity of a human being and the goodness of human nature even though this nature can be distorted by crime. Therefore, the main emphasis of this book is on rehabilitation of criminal offenders. Among various themes of rehabilitation, the reader will find an in-depth discussion of religion as a crime preventing factor. Repentance of criminal offenders is explored in the context of criminal laws of Thailand, China, Germany and other countries.