This paper tells Rational actor model of crime and criminal behaviour is based on the notion of free will, it proposes that human beings choose to commit criminal behaviour and can be deterred through the threat of punishment. Biological Approach: It proposes that human beings commit crime because of internal factors over which they have little or no control.Causal Approach: This is a study of the causal link that exists between the defendant’s action and the plaintiff’s injury. It is observation of facts in relation to phenomenon of crime interpreting them in relation to the possible causes of criminal behaviour. A cause may be necessary or sufficient. If result B invariably follows cause A without any other factors being required, and cause A cannot be replaced by any other alternative, then cause A is both sufficient and necessary cause. Deficient in Probity Approach: The criminals deficient in probity, says Dr. Maurice Parmellee, commit crimes against property. Descriptive Approach: It describes the phenomenon of crime and those who commit it. It covers all aspects such as personal traits of criminal and the various forms of criminal behaviour. Organically Inferior human traits Approach: This study was carried by Eavert A. Hootan and William H. Sheldon. Hootan stated that criminals are organically inferior. Hootan had studied 13,873 male criminals and 3023 persons of control group. The study was conducted in various American States. To Hootan the criminal is and inadequately developed runty fellow, while to Sheldon the criminal is husky and athletic type fellow. Economic Approach: It studies external economic factors.Endemic Approach: It studies those factors that arise from local conditions or belong to a particular period of the year, or the specified area that make a man criminal.Environmental Approach: It seeks to explain the phenomenon of criminal behaviour with reference to factors outside the personality of the delinquent.Functional Psychosis Approach: As to mental quality an offender is either normal or abnormal. The Psychotics are of two types, having psychosis of organic origin and having psychosis of non psychosis origin or functional psychosis. General paralysis of the insane (Patients of this abnormality commit offences with astonishing openness and silliness);Traumatic psychosis (Patients of this abnormality commit crimes of violence);Encephalitis Lethargic (Patients of this abnormality commit crimes of explosive and sexual nature);Senile Dementia (patients of this abnormality are of old age and commit varying crimes);Epilepsy (Patients of such abnormality commit crimes of sudden violence).Schizophrenia (Patients of this abnormality suffer split-mindedness. Geographical Approach: George B, Vold’s Approach: In his famous treatise known as Theoretical Criminology, George Bryan Vold, says: Heredity and Criminal Families Approach: Studies were conducted by Arthur Dugdale in the United States of America on the Jukes (1877) and by Henry Herbert Goddard on the Killikaks (1912). Individualistic Approach: It focuses its attention on the biological, mental and other characteristics of the offender to explain the cause of his delinquent behaviour. Professor Ahmad Siddiq’s conclusion on individualistic approaches is logical and appealing to reason. Normative Approach: Objective Approach: It is an approach to criminology as to “what ought to be?” Objective Approach: Criminal behaviour when explained in terms of factors extraneous to the offender which are social, sociological, cultural and economic, the approach is called objective. Organic Psychosis Approach: General paralysis of the insane (Patients of this abnormality commit offences with astonishing openness and silliness);Traumatic psychosis (Patients of this abnormality commit crimes of violence);Encephalitis Lethargica (Patients of this abnormality commit crimes of explosive and sexual nature);Senile Dementia (patients of this abnormality are of old age and commit varying crimes);Epilepsy (Patients of such abnormality commit crimes of sudden violence).Physiological Approach: It is an approach to criminology made by endocrinologists who found that glandular malfunctioning caused the delinquent behaviour. Social Approach: Man may live in isolation but generally he lives in society. Subjective Approach: Criminal behaviour when explained in terms of factors within criminal, i.e. physical, biological and mental traits, the approach is called subjective approach to Criminology. Therapeutic Approach: This approach is of recent origin. It considers the criminal as a victim of circumstances and a product of various factors within the criminal and the society. It is called therapeutic approach. Twin Research Approach: Violent due to environmental influences as prejudices of honour, politics and religion, approach.