It is most often used in reference to cases where a person is granted permission to work in a country where they do not have citizenship, but it is also used in reference to minors, who in some jurisdictions require a permit to work legally due to child labor laws. A work permit may be required within an industry, sector, or occupation to perform certain functions in a factory outside of normal operational duties (such as maintenance work). In some places, it is called a Permit to Work (PPT).
In general, the United States does not require a work permit for adult citizens. However, it does require certain foreign nationals to have an Employment Authorization Document from the United States Citizenship and Immigration Services (USCIS), part of the U.S. Department of Homeland Security (DHS).
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