In this entry, for reasons of space, we have focused primarily on the moral principles that govern the objective (or fact-relative) permissibility of defensive harm. Of course, this leaves open questions about how defensive agents ought to act in light of their evidence and under conditions of uncertainty. While the majority of the debate has also centered on questions of objective permissibility, there is growing literature exploring the subjective (or evidence-relative) ethics of defensive harm (and non-consequentialist moral principles more generally) (see, for example, Tomlin 2019; Haque 2017; Bolinger 2017, 2021, forthcoming; Frowe 2010; Lazar 2018, 2019a, 2019b; van der Vossen 2016).