To practice comparative law is a way to know more about foreign law. It is necessary to know about foreign law in lots of fields, such as penal law, elaboration of supra national laws, international companies law or private international law. Private international law is a part of a national law that defines which law is applicable to a situation involving one or several foreign element. The foreign element may be a person involved or the country where a legal situation arise. In other words, private international law will lead to choose between different legal systems. A legal system is a set of coordinated rules. In private international law, it is necessary to know about foreign law under two aspects.
On one hand, private international law may lead to apply foreign law. It will be necessary to know about foreign law in such a situation thereof.
On the other hand, it is necessary to know about foreign law in order to elaborate private international law. Private international law has to be as fair as possible in the choice of one law instead of another. Indeed, private international law has to protect the legal system it comes from in applying national law. But it as to protect itself in applying foreign law as well. Indeed, if there is no place left for foreign law, the country applying its private international law might have some political troubles with the foreign country or with its foreign inhabitants. In order to give a place to foreign law in its private international law, the law-makers will have to look at foreign law e.g. to know the importance of the application of a particular rule in the foreign legal system. A globalization movement is occurring nowadays. That is people move more and more easily. Therefore, there are more and more foreign elements in a particular legal system. So private international law is becoming more and more important, and has to be widened and adapted to this new situation. A very good example of this