Purgatory, when defined by that term, is a concept unique to Roman Catholicism. It has a central role in the structure of salvation and the after-life, as it posits that men undergo a purification of some kind after death but before entrance into Heaven. As with most things related to Christian doctrine, it is particularly defined, yet because of the imperfect nature of human understanding, it is often misunderstood, whether by critics who aim to refute aspects of the theology they mistakenly attribute to it, or proponents who harm the theology by invoking principles unrelated to its defense. The aim of this article, therefore, is to provide a clear Roman Catholic perspective on purgatory founded upon the doctrine of the Church. The intent is not to enter into the particular nature of purg