Recent events have revived questions about the circumstances that ought to trigger therapists’ duty to warn or protect. There is extensive interstate variation in duty to warn or protect statutes enacted and rulings made in the wake of the California Tarasoff ruling. These duties may be codified in legislative statutes, established in common law through court rulings, or remain unspecified. Furthermore, the duty to warn or protect is not only variable between states but also has been dynamic across time. In this article, we review the implications of this variability and dynamism, focusing on three sets of questions: first, what legal and ethics-related challenges do therapists in each of the three broad categories of states (states that mandate therapists to warn or protect, states that permit therapists to breach confidentiality for warnings but have no mandate, and states that give no guidance) face in handling threats of violence? Second, what training do therapists and other professionals involved in handling violent threats receive, and is this training adequate for the task that these professionals are charged with? Third, how have recent court cases changed the scope of the duty? We conclude by pointing to gaps in the empirical and conceptual scholarship surrounding the duty to warn or protect.