Prolonged grief disorder (PGD) is a distinct diagnostic entity that has recently garnered considerable attention as it describes an intense, enduring, distressing and disabling bereavement reaction experienced by a small minority of community-based mourners. In recent decades, research has exploded to address how best to treat PGD with different psychotherapeutic interventions. In this state-of-the-science review, the strength of the evidence will be discussed regarding common psychotherapeutic interventions used to treat grief. Specifically, we focus on the most commonly used interventions, cognitive behavioral (CB)-based therapies, bereavement and support groups, and brief contact interventions (BCIs), in an effort to summarize the relevant clinical takeaways of the current available research. A discussion of the use of these therapies in specific clinical populations is also included, with a focus on those traumatically bereaved, pediatric populations, communities of color, and underserved communities. Important foci and directions for future research are also discussed.