Incendiary weapons produce heat and fire through the chemical reaction of a flammable substance. Among the cruelest weapons used in contemporary armed conflict, they inflict excruciating burns, which sometimes penetrate to the bone, and can cause respiratory and organ damage, permanent disfigurement, and psychological trauma. They also destroy civilian structures. Protocol III to the Convention on Conventional Weapons (CCW), adopted in 1980, regulates incendiary weapons but has loopholes that reduce its legal and normative power. It excludes multipurpose munitions that have the same incendiary effects as those covered by the protocol and contains weaker regulations for ground-launched models than air-dropped ones. Human Rights Watch, which has spearheaded efforts in this area, and other nongovernmental organizations have urged states to close those loopholes. Although consensus requirements have slowed progress, CCW states parties have expressed significant support for revisiting and strengthening Protocol III.