This article comments on 4 uses of the slippery-slope concept: principle of consistency; argument that if an act is carried out once, it is more likely that it & related acts will be carried out again; likelihood that care providers who perform an act once would be more psychologically inclined to do so again; &, improper reasoning that deprives patients of pain relief that otherwise would be given. The issue of physicians acting collectively on the basis of moral conscience is also discussed.