This paper describes the theoretical background and procedures (including psycho-education, screening, treatment protocol and outcome measurement) involved in a protocol-driven internet treatment of post-traumatic stress and grief in a group of people who have suffered from mild to relatively severe trauma. The paper examines the results of 3 outcome and process studies, which were carried out initially in a student population and subsequently in the general population of highly traumatized people. In the latter study, participants in the experimental condition (n = 69) improved significantly more than participants in the waiting list control condition (n = 32), with respect to trauma-related symptoms and general psychopathology. The effect sizes were large. More than 50% of the participants treated showed reliable change and clinically significant improvement after treatment for avoidance and depression. Treatment proved most beneficial for participants who had suffered from intentional trauma and those who had not previously discussed the traumatic events with significant others. Content analysis of the publications indicates a remarkable increase in cognitive coping during treatment. The possibilities for future research into internet-driven treatment of post-traumatic stress symptomatology are discussed, including the proposal to study the effects of sending a final written letter to a significant other person.