• acceptance and commitment therapy;
  • anxiety disorders;
  • cognitive behavioral therapy;
  • mediation;
  • treatment mechanisms

Cognitive behavioral therapy (CBT) and acceptance and commitment therapy (ACT) researchers and scholars carry assumptions about the characteristics of these therapies, and the extent to which they differ from one another. This article examines proposed differences between CBT and ACT for anxiety disorders, including aspects of treatment components, processes, and outcomes. The general conclusion is that the treatments are more similar than distinct. Potential treatment mediators and issues related to the identification of mediators are considered in depth, and directions for future research are explored.