Emergency on-farm euthanasia of livestock is required when animals are severely injured, chronically ill, or unable to reach slaughter. The ability to perform prompt, effective euthanasia is a fundamental welfare competency for all livestock producers. Delay in euthanasia for economic reasons (waiting for a buyer, avoiding losses) represents a significant welfare failure. Approved methods vary by species: penetrating captive bolt followed by exsanguination for cattle and pigs; pithing is now prohibited in most countries. Firearm use requires training in appropriate calibre, placement, and safety. Injection of barbiturate overdose requires veterinary administration. Research identifies delayed euthanasia as the most common welfare failure in livestock emergencies. Farm assurance programmes increasingly require documented euthanasia protocols, on-farm equipment availability, and stockperson competency assessment. AVMA and BVAA guidelines provide species-specific protocols.