The profession of private investigator is defined by the Law of 19th July 1991 which specifies that the private investigator has the task of collecting information in defense of the interests of his clients in the search for missing persons or lost or stolen property, the collection of information relating to civil status, conduct, morality and solvency of persons, to gather evidence or to establish facts which give rise to or may give rise to conflicts between various parties or can be used to put an end to these conflicts, to look for evidence of industrial espionage... The investigator is subject to the duty of confidentiality and his investigation reports are admissible in court.

Investigators are required to meet the established requirements for training and professional experience. In other words, the private investigator is not authorised to practise if he has not successfully completed the 2 year training course approved by the Minister of the Interior. Moreover, the investigator will lose the right to exercise the profession if he neglects to follow the required five-year retraining in time.

Finally, before being able to practice his profession, the private investigator must obtain authorisation from the Interior Ministry (Home Office). Such authorisation is a necessary but not sufficient condition for effective research activities. The investigator can start his work only when he is also in possession of an ID card. The authorisation is necessary not only for the right to work, but also for the simple fact of being able to present oneself as a private investigator.