Parole is the early release of a prisoner who agrees to abide by certain conditions, originating from the French word "parole" ("speech, spoken words" but also "promise"). The term became associated during the Middle Ages with the release of prisoners who gave their word.

This differs greatly from pardon, amnesty or commutation of sentence in that parolees are still considered to be serving their sentences, and may be returned to prison if they violate the conditions of their parole.

Development of modern parole.

Alexander Maconochie, a Scottish geographer and captain in the Royal Navy, introduced the modern idea of parole when, in 1840, he was appointed superintendent of the British penal colonies in Norfolk Island, Australia. He developed a plan to prepare them for eventual return to society that involved three grades. The first two consisted of promotions earned through good behaviour, labour, and study. The third grade in the system involved conditional liberty outside of prison while obeying rules. A violation would return them to prison and they would start all over again through the ranks of the three-grade process. He reformed its ticket of leave system, instituting what many consider to be the world's first parole system. Prisoners served indeterminate sentences from which they could be released early if they showed evidence of rehabilitation through participation in a graded classification system based on a unit of exchange called a mark. Prisoners earned marks through good behavior, lost them through bad behavior, and could spend them on passage to higher classification statuses ultimately conveying freedom.

In an instance of multiple discovery, in 1846, Arnould Bonneville de Marsangy proposed the idea of parole (which he termed "preparatory liberations") to the Civil Tribunal at Reims.