Applied Relaxation (AR), originally developed by Lars-Göran Öst, is a long standing, efficacious treatment for generalized anxiety disorder (GAD). While newer treatments are continuing to be developed, AR remains one of the most efficacious treatments for GAD. However, AR has received less in-depth attention more recently, particularly in terms of potential mechanisms of action. This paper is written to honor the development and history of AR and to highlight the ways that it has continued to be adapted. In this paper, the AR treatment strategies are presented, which include: noticing early signs of anxiety, learning relaxation skills, and applying relaxation at the first sign of anxiety. Then, additional adaptations to AR are presented along with recommendations of how AR may be enhanced by understanding potential mechanisms of change. Finally, recommendations are made for the continued evolution of AR as a powerful and efficacious treatment for GAD.