Are the sources of a combatant's knowledge in war morally relevant? This article argues that privacy is relevant to just war theory in that it draws attention to privacy harms associated with the conduct of war. Since we cannot assume that information is made available to combatants in a morally neutral manner, we must therefore interrogate the relationship between privacy harms and the acts that they enable in war. Here, I argue that there is ample evidence that we cannot discount (...) the analysis of privacy harms in war, and that analysis of such harms requires us to examine social goods. I develop this point to demonstrate the problems that this poses for aspects of revisionist just war theory; namely, reductivism and individualism. In order to evaluate the moral consequences of privacy harms in war, we must understand the unilateral and adversarial character of balancing privacy harms against social goods in the context of war, which, in turn, requires that we consider social goods and social institutions as objects of moral evaluation. Further, concepts drawn from privacy scholarship, such as Helen Nissenbaum's concept of contextual integrity, enable us to identify a range of moral problems associated with contemporary war that deserve further attention from just war theorists. (shrink)