Situations in which good can be secured for some people only if others suffer harm are of great significance to moral theory. Consequentialists typically hold that the right thing to do in such cases is to maximize overall welfare. But nonconsequentialists think that many other factors matter. Some, for example, think that in situations of conflict it is often more acceptable to let a certain harm befall someone than actively to bring the harm about. I believe that this view, which I call the Doctrine of Doing and Allowing, is correct, and I defend it elsewhere. But there is a different and even better known anticonsequentialist principle in the Doctrine of Double Effect (for short, the DDE). According to one of the common readings of this principle, the pursuit of a good tends to be less acceptable where a resulting harm is intended as a means than where it is merely foreseen. It is this controversial idea that I wish to examine here.

There are two major problems with the DDE. First, there is a difficulty in formulating it so that it succeeds in discriminating between cases that, intuitively speaking, should be distinguished. In particular, I will need to find a formulation that escapes the disturbing objection that under a strict enough interpretation the doctrine fails to rule against many or most of the choices commonly taken to illustrate its negative force. Second, there is a question of rationale. What, apart from its agreeing with our particular intuitions, can be said in favor of the doctrine?