An amphibious vehicle is a transport able of moving both on land and on water. In these last years, the ability of autonomous and semi-autonomous amphibious vehicles to operate in harsh environments is becoming increasingly important for military and civilian operations. Apart from the size of the vehicles, they can be divided into two broad categories: Hovercraft and all those vehicles that can operate not only on water, but on multiple terrains (all-terrain) such as ice, snow and mud. Some of them are based on tracked or wheeled movements; there is also a “screw” configuration used for muddy soils. In some cases, when vehicles are heavier than water, therefore unable to float, rigid or inflatable floats are applied. For propulsion in water, propellers or ducted propellers are used, or the rotation of the wheels themselves or of the tracks is exploited. In this chapter some amphibious vehicles, both civil and military will be presented.