The present study investigates the efficacy of an Internet-based cognitive-behavioral therapy program for bereaved people suffering complicated grief. The program combines established methods of psychotherapy with new technology--therapists and patients communicated exclusively by e-mail. Bereaved individuals diagnosed with complicated grief (n = 55) were randomly assigned to either the treatment group or a waiting list control condition. The 5-week intervention consisted of three modules: (1) exposure to bereavement cues; (2) cognitive reappraisal; and (3) integration and restoration. The Impact of Event Scale (IES), a failure to adapt scale, and the depression and anxiety subscales of the Brief Symptom Inventory (BSI) were used to assess treatment outcomes. Participants in the treatment group (n = 26) improved significantly relative to participants in the waiting condition on symptoms of intrusion, avoidance, maladaptive behavior, and general psychopathology, and showed a large treatment effect. Follow-up results show that this improvement was maintained after 3 months. (Contains 5 tables, 1 figure, and 1 footnote.)