When a transportation movement requires two or more carriers, and the carriers have agreed to a special joint through rate – a single rate is published to cover the interline movement. A distinction should be made between a joint rate and through rate, however. A through rate is the result of an expressed or implied agreement. A through rate may be joint rate or a combination of local or joint rates. It is a well established principle that a joint through rate is the only legal rate between the points where it is unconditionally established. It will take precedence over any combination of intermediate rates between the given points. However, a tariff may provide that the aggregate of the intermediate rate is applicable. Under these circumstances, is a combination of several intermediate rates is lower than a through rate, it is applicable.