Brain drain is understood to mean the emigration of highly qualified workers from their countries of origin. A distinction is made between two different phenomena:
1. External brain drain is understood to mean the migration of highly qualified workers from developing countries who do not offer any employment opportunities or who only have very poor working conditions.
2. If scientists in developing countries deal with problems that mainly affect industrialized countries, one speaks of internal brain drain.
Both phenomena worsen the chances of a change in the economic situation in developing countries.