The Nightingale Pledge, named in honour of Florence Nightingale, is a modified version of the Hippocratic Oath. Lystra Gretter and a Committee for the Farrand Training School Grace for Nurses in Detroit, Michigan created the pledge in 1893. Gretter, inspired by the work of Nightingale, the founder of modern nursing, credited the pledge to the work of her committee, but was herself considered "the moving spirit behind the idea" for the pledge.

The Hippocratic Oath is an oath of ethics historically taken by physicians. It is one of the most widely known of Greek medical texts. In its original form, it requires a new physician to swear, by a number of healing gods, to uphold specific ethical standards. The oath is the earliest expression of medical ethics in the Western world, establishing several principles of medical ethics which remain of paramount significance today. These include the principles of medical confidentiality and non-maleficence. As the seminal articulation of certain principles that continue to guide and inform medical practice, the ancient text is of more than historic and symbolic value. It is enshrined in the legal statutes of various jurisdictions, such that violations of the oath may carry criminal or other liability beyond the oath's symbolic nature.