According to the Doctrine of Doing and Allowing, the distinction between doing and allowing harm is morally significant. Doing harm is harder to justify than merely allowing harm. This paper is the first of a two paper critical overview of the literature on the Doctrine of Doing and Allowing. In this paper, I consider the analysis of the distinction between doing and allowing harm. I explore some of the most prominent attempts to analyse this distinction: Philippa Foot’s sequence account, Warren Quinn’s action/inaction account, and counterfactual test accounts put forward by Shelly Kagan and Jonathan Bennett. I also discuss Jeff McMahan’s account of the removal of barriers to harm. I argue that analysis of the distinction has often been made more difficult by two mistaken assumption: (a) the assumption that when an agent does or allows harm his behaviour makes the difference to whether or not the harm occurs; (b) the assumption that the distinction between doing and allowing and the distinction between action and inaction are interchangeable. I suggest that Foot’s account is the most promising account of the doing/allowing distinction, but that it requires further development.