Locating missing participants in countries outside of the US involves a different expert skill set and knowledge compared to domestic US location work. When locating lost participants within the US, service companies enjoy access to nationwide databases, Freedom of Information Act, one legal system (excluding Louisiana) and one main language.
This is much different than locating lost participants outside of the US. Additional challenges facing foreign reunification and communication efforts include multiple language and cultural differences, a plethora of legal systems, various privacy laws and a lack of centralized foreign database.