| Term | Definition | Status |
| Terminating life-sustaining treatments | When the physician withholds or withdraws life-sustaining treatments, such as a respirator, vasopressors, or artificial nutrition and/or hydration from the patient with the patient or proxy's consent | Legal and ethical in the United States and most other developed countries |
| "Double effect" of opioids for pain or dyspnea | When the physician administers narcotics or other medications to relieve pain or other symptoms "foreseeing but not intending" that this may cause respiratory depression or other side effects that might increase the risk of the patient's death | Legal and ethical in the United States and most other developed countries |
| Physician-assisted dying (also called physician-assisted suicide, physician aid in dying, patient-administered physician-hastened death, self-administered medical assistance in dying and medical aid in dying) | When the physician provides medication, a prescription, and information on its use to a patient at their request with the understanding that the patient potentially intends to use them to end life | Legal in California, Colorado, District of Columbia, Hawaii, Maine, Montana, New Jersey, New Mexico, Oregon, Vermont, and Washington; also legal in Belgium, Canada, Colombia, Germany, Luxembourg, the Netherlands, New Zealand, Spain, Switzerland, and three states in Australia (Tasmania, Victoria, and Western Australia) |
| Voluntary active euthanasia (also called physician-administered hastened death, and clinician-assisted medical assistance in dying) | When the physician or someone else administers medications, such as sedatives and paralytics, to intentionally cause the patient's death at the patient's explicit request with full informed consent | Legal in Belgium, Canada, Colombia, Luxembourg, the Netherlands, New Zealand, and Spain; and, if patient is unable to self-administer, Tasmania (Australia), Victoria (Australia) and Western Australia (Australia) |
