Tort law draws a fundamental distinction between doing harm and failing to prevent it. Generally, there is no positive duty upon private individuals to prevent harm. However, there are instances in which a failure to prevent harm—an omission—can have legal consequences.Omissions in Tort Law analyses the distinction drawn by tort law and argues that it is not best understood in terms of the distinction between acts and omissions, but in terms of making things worse versus not making things better. It considers when the law will and should impose duties to improve another's position. It provides novel conceptual analyses of the basic concepts that inform the imposition of positive duties, such as creation of risk, interfering with aid, assuming responsibility, controlling a source of risk, and the normative considerations that underpin them. It considers the ways in which the law differentiates between actively causing harm and failing to protect from harm, and makes recommendations as to how the law could be improved. Exploring the ways in which conceptions of morality intersect with legal obligations, Omissions in Tort Law offers a detailed and nuanced perspective on omissions and positive duties.