When an importer finds a cheaper price of a good or equivalent good on the world market and imports the good instead of paying higher local prices. These imports tend to be outside authorized importer channels, and are often carried by ordinary tourists. Goods that do not incur heavy transportation costs are most at risk from parallel imports. Authorized retailers, who are not allowed to source goods from parallel importers, generally oppose this practice since it makes them non-competitive against unauthorized retailers who can source these relatively cheap goods.