The death of a loved one is a universal experience, and marker of the human condition. Grief, the cognitive, emotional, and behavioral responses to bereavement, is both a ubiquitous and a unique psychological process. Thus, health providers often find themselves in a dilemma, caught between the need to alleviate an individual's distress and impairment, and the danger of overly "pathologizing" their grief reaction. This chapter reviews how acute grief reactions generally evolve over time, the clinical presentation of complicated grief, and finally, other psychiatric disorders that might develop or be precipitated in the aftermath of the death of a loved one, particularly prolonged grief disorder.