In this article, I present a novel argument against abortion. In short, what makes it wrong to kill someone is that they are a counterfactual person; counterfactual persons are individuals such that, were they not killed, they would have been persons. My view accommodates two intuitions which many views concerning the wrongness of killing fail to account for: embryo rescue cases and the impermissibility of infanticide. The view avoids embryo rescue cases because embryos in the rescue scenarios are not counterfactual (...) people: they are not counterfactual people because it is false to say that, were they not killed, they would have been persons. As a result, it does not follow from my account that there is a prohibition against allowing embryos to die. On the other hand, infants are counterfactual people: an infant is an individual such that, were she not killed, she would have been a person. (shrink)