Moral blackmail is a wrongful strategy intended to force a person to perform an act by manipulating her circumstances so as to make it morally wrong for her to do anything else. The idea of moral blackmail can seem paradoxical, but moral blackmail is a coherent and indeed a familiar phenomenon. It has special significance for our intimate personal relationships and is often a force within family dynamics. It is used to enforce power relationships within families, and in particular to uphold expectations that women and girls will do most of the work in caring for vulnerable family members. It is also used as a tool of policy makers, to transfer to families duties of care that would otherwise be discharged by the government or by society at large. It is an important but under-recognized source of ongoing manipulation and exploitation.