The terms "designated driver" and "designated driving" (commonly known as DD) refer to the selection of a person who remains sober as the responsible driver of a vehicle whilst others have been allowed to drink alcoholic beverages.
Thus, as a practical and ethical matter a designated driver is a person who abstains from alcohol on an occasion in order to drive their companions home safely as an alternative to driving under the influence. In order to encourage these arrangements, some bar, restaurant and nightclub proprietors will offer free or reduced-price soft drinks to designated drivers.[1]