Geriatric assent involves health care professionals' active collaboration with cognitively impaired patients that takes account of their longstanding values in any major health care decisions. The main purpose of this paper is to assist geriatric health practitioners 'in the field' to understand how to apply geriatric assent in a variety of clinical situations to maximize incapacitated older adults' input into decision-making. A case example and algorithm are presented to illustrate the basic principles of implementing geriatric assent. Practice informed by the principles of geriatric assent will preserve respect for the current and future autonomy of patients across diverse cultural backgrounds.