The protection regimes of international human rights law (IHRL) and international humanitarian law (IHL) partially overlap. Certain unwanted conduct may therefore violate both human rights norms and humanitarian law rules. For the purposes of international criminal law (ICL), such conduct may therefore qualify as both a crime against humanity and a war crime. The present contribution discusses the interplay between the crimes against humanity and war crimes regimes, including the impact of the existence of an armed conflict on the status of alleged victims of crimes against humanity. It further highlights the risk that certain acts that form part of military operations in times of armed conflict may be qualified as crimes against humanity even though they are not contrary to IHL. The author concludes that crimes against humanity and war crimes have to be considered with care, and kept separate when necessary, in order to avoid any negative impact on the development of IHL and/or IHRL, and to safeguard the rights of the accused under ICL.