Ross's prima facie duty theory was developed & presented in 1930 by W. D. Ross in his book The Right and the Good . In this book Ross presents an ethical theory which attempts to join the ideas of Utilitarianism with those of Kantianism. Ross maintained that people are often aware of a number of obligations in situations, some of which are conflicting. Therefore, Ross believed that we must always weigh options when deciding which action is morally correct.

In this way a health professional would weigh each course of action, and then observe if that action would fulfill a 'prima facie' duty or not. He maintained that, if a moral action fulfilled a prima facie duty, then that duty became an actual duty and the person needed to carry out the action to be morally correct.

In addition, if more than one prima facie duty is recognized in a moral problem, the health professional needs to sort and weigh them all before deciding which action is morally correct. The prima facie duties are: fidelity, gratitude, justice, beneficence, self-improvement, & nonmaleficence.

According to Ross, the action that would be morally correct is the one that would fulfill the greatest balance of the prima facie rightness to prima facie wrongness.