Military medical personnel and objects, as well as wounded and sick combatants, are protected against direct attack under the principle of distinction in international humanitarian law. However, some authors argue that they are not covered by the principles of proportionality and precautions. This opinion note explains that military medical objects constitute civilian objects under the rules governing the conduct of hostilities. It also demonstrates that, in view of the object and purpose of the First Additional Protocol to the Geneva Conventions, expected incidental casualties of military medical personnel and wounded and sick combatants must be included among the relevant incidental casualties under the principles of proportionality and precautions. This stems in particular from the interpretation of the obligation ‘to respect and protect’ as the overarching obligation of the special protection afforded to all medical personnel and wounded and sick. Support for this conclusion can be found in a number of military manuals and in the Additional Protocol’s preparatory work and Commentaries. This conclusion also reflects customary law.