Although dependency in its various forms has been widely studied, most investigations examine manifestations of dependency within individuals. Scrutiny of the literature reveals that synergistic dependencies—situations wherein both members of a dyad manifest excessive dependency of one form or another—play a role in some forms of partner and elder abuse. High levels of interpersonal or economic dependency in a woman coupled with high levels of interpersonal dependency in her male partner increase the likelihood of partner abuse. When family member caregivers are economically dependent on a functionally dependent older adult, risk for elder abuse increases. Although these synergistic dependencies differ across abuse domains, two prevailing themes emerge. The interpersonal, economic, and functional dependencies of abused partners and older adults are associated with feelings of helplessness, powerlessness, and an inability to challenge the abuser. The common dependency-related dynamic in perpetrators of abuse is fear—fear of abandonment leading to partner abuse, and fear of loss of financial support increasing risk for elder abuse.