Following the death of a loved one, a small group of grievers develop an abnormal grieving style, termed complicated or prolonged grief. In the effort to establish complicated grief as a disorder in DSM and ICD, several attempts have been made over the past two decades to establish symptom criteria for this form of grieving. Complicated grief is different from depression and PTSD yet often comorbid with other psychological disorders. Meta-analyses of grief interventions show small to medium effect sizes, with only few studies yielding large effect sizes. In this article, an integrative cognitive behavioral treatment manual for complicated grief disorder (CG-CBT) of 25 individual sessions is described. Three treatment phases, each entailing several treatment strategies, allow patients to stabilize, explore, and confront the most painful aspects of the loss, and finally to integrate and transform their grief. Core aspects are cognitive restructuring and confrontation. Special attention is given to practical exercises. This article includes the case report of a woman whose daughter committed suicide.