Spouse killers differ from perpetrators of anonymous crimes of violence in several ways. The spouse killer is older and has a less serious criminal record than other murderers; they react favorably to psychiatric treatment. Particular attention is focused on the pre-spouse killing syndrome in which the partners exist in symbiotic isolation relationship characterized by narcisstic features. Each partner has a fixed role. Because separation is unbearable for the dependent partner, violence can erupt upon introduction of a third person and the subsequent disturbance of the unstable balance. Professionals who deal with potential spouse killers (family doctor, police, or public prosecutor) are advised to maintain a more active attitude. 5 notes and 14 references (Author abstract modified)