Open border

An open border is a border that enables free movement of people between different jurisdictions with limited or no restrictions on movement, that is to say lacking substantive border control. A border may be an open border due to a lack of legal controls or intentional legislation allowing free movement of people across the border (de jure), or a border may be an open border due to lack of adequate enforcement or adequate supervision of the border (de facto). An example of the former is the Schengen Agreement between most members of the European Economic Area (EFTA and the EU). An example of the latter has been the border between Bangladesh and India, which is becoming controlled. The term "open borders" applies only to the flow of people, not the flow of goods and services.

Open borders are the norm for borders between subdivisions within the boundaries of sovereign states, though some countries do have controlled borders within the boundaries of the state (for example in the People's Republic of China between the mainland and the administrative regions of Hong Kong and Macau). Open borders are also usual between member states of federations (such as the United States of America) and confederations such as Switzerland, though again in some instances movement between member states may be controlled via an internal passport system. Federations and confederations typically maintain external border controls through a collective border control system, though they sometimes have open borders with other non-member states through special international agreements.

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