<p>Heterogeneity is well established in sexual homicide research, but most conceptual models of sexual homicide include only a single developmental trajectory and assume inevitability of fatal outcomes. Higgs and Stefanska (2018) proposed an empirically based multi-trajectory model of sexual aggression with fatal and non-fatal outcomes. The present study tested this model with an independent sample of 205 men who had committed sexual assaults against women, including 37 sexual homicides. Structural equation modeling identified two main trajectories, thus partially confirming the multi-trajectory model. The first trajectory was characterized by internalized problems (e.g., low self-esteem, loneliness, rape-related sexual fantasies) that began before the age of 18, persisted into adulthood, and culminated in sexual homicide. The second trajectory, on the other hand, was characterized by externalized problems (e.g., antisocial attitudes and behaviors, psychoactive substance use) across adolescence and adulthood, culminating in rape, which may result in the victim’s death. The theoretical and clinical implications of these developmental trajectories are discussed.</p>