If you signed an Advance Directive in another state, which provides for the withholding or withdrawal of life-sustaining treatment or for the appointment of another to provide, withhold or withdraw life-sustaining treatment, and that document complied with the law of the state in which signed, it is valid in Oklahoma to the extent it does not exceed authorizations under Oklahoma law. However, Oklahoma residents should sign an Advance Directive that complies with the Oklahoma law if at all possible.