Ballism is defined as a movement disorder characterized by involuntary, forceful, flinging, high-amplitude “throwing” movements. Ballism is often accompanied by choreatic movements, the latter being more distal whereas ballism describes the proximal movements. With time, the proximal ballistic movements may become less pronounced, and the distal choreatic movements predominate. Ballism increases with action and is absent during sleep. The movements can be so violent that patients injure themselves. Ballism usually affects one side of the body, and it is then referred to as hemiballism. Older terms are hardly ever used anymore – that is, monoballism if only one limb is affected, biballism if both extremities on one side of the body but not the head or face are affected, or paraballism if both sides of the body are affected.