Although the word 'euthanasia', a compound word of eu- (good, well) and thanatos (death) is widely known, it is greatly misunderstood. With regard to end-of-life medicine, several phrases, including death with dignity, passive euthanasia, and natural death also need to be clarified. A review of their meanings and connotations is provided along with a brief history of the discussion in Korea on forgoing life support. Korea has no law regarding the cessation of artificial ventilation, but several judgments of law courts provide us with a general principle that cessation could be applied if the patient is in an irreversible or dying condition medically, and has presented his or her intention with something like an advance directives, or is reasonably presumed to have such a will.