Passive euthanasia refers to the practice of allowing a person to die by withholding or withdrawing medical treatment that is necessary to sustain life. This can include stopping life-support systems or not administering medications that would prolong life. The intention is not to cause death directly but to respect the natural process of dying. In many countries, passive euthanasia is legally and ethically accepted under certain circumstances, especially when a patient is in a persistent vegetative state or has a terminal illness. It often involves discussions about patient autonomy and the right to refuse treatment, emphasizing the importance of informed consent.