An Interplanetary Mission is a voyage or trip through space involving more than one planet. This is an important distinction because it requires significantly more ?V (change in velocity) than do missions within a single planetary system.

As of this date in 2005, all manned missions have been within the Earth's planetary system (i.e. to the moon or closer). Quite a few robotic interplanetary missions have been performed by the USA, the Soviet Union (and later by Russia), Japan and the European Union.

NASA has hopes that it will be able to launch a manned interplanetary mission to Mars by some time after 2015. The European Space Agency has the long-term vision of sending a human mission to Mars by 2030 under the Aurora Programme.

See also: Timeline of planetary exploration.