Every country regulates the migration of people across its international borders. Some even exercise control over movements within their borders.  Some aspects of immigration are common around the world, e.g. governments issue passports to their own citizens and issue documents granting foreign nationals permission to visit, live, study and/or work within their borders for certain periods of time; while other aspects can vary greatly from one country to the next, e.g. how the country treats citizens of close neighbors or other countries, taxation of foreign nationals and the paperwork and procedures for applying for a “visa” or other documents.  This section provides links to resources about immigration in many countries.