Elder mistreatment inquiry is a relative newcomer to the family violence arena and its empirically-based knowledge lacks a theoretical framework within which to understand its multiple manifestations. Effective intervention and prevention strategies depend upon theory-driven hypotheses testing in order to understand how risk factors at various social-ecological levels interact in the etiology of elder mistreatment. To foster theoretical model development, this article: (1) takes inventory of the empirically-derived knowledge on elder mistreatment; (2) reviews the major theoretical approaches to the etiology of elder mistreatment; (3) proposes a new model of elder mistreatment of older adults with cognitive impairment. Each component of the NIJ-funded work was heavily informed by the methods and models from the adjacent areas of inquiry, child maltreatment and intimate partner violence. Information was obtained through an extensive literature review of the criminal justice, psychology, sociology, gerontology, forensics, and public health literature as well as from interviews with experts from elder mistreatment, child maltreatment, and intimate partner violence.