Deontology and utilitarianism differ in their approaches to ethical decision-making. Deontology, associated with Immanuel Kant, emphasizes adherence to moral duties and rights, regardless of consequences. It provides clear ethical guidelines but can lead to negative outcomes if rules are followed rigidly. For example, a deontologist would tell the truth to a dangerous person searching for a friend, prioritizing honesty over potential harm.

Utilitarianism, linked to Jeremy Bentham and John Stuart Mill, focuses on the consequences of actions, aiming to maximize overall happiness. It is flexible and practical but can justify actions that violate individual rights. In the same scenario, a utilitarian would lie to protect their friend, prioritizing the prevention of harm over strict honesty.

In medical ethics, a deontologist might refuse euthanasia to preserve life, while a utilitarian might support it to alleviate suffering. In environmental policy, a deontologist might enforce strict pollution controls based on duty, while a utilitarian might balance economic benefits with environmental impact.

Each theory has merits and limitations, highlighting the importance of context in ethical decision-making.