Background: Although cognitive-behavioral therapy (CBT) is efficacious in the treatment of generalized anxiety disorder (GAD), many individuals remain symptomatic following treatment, indicating a need for further treatment development. As a result, many researchers have developed unique cognitive-behavioral therapies that highlight specific targets for intervention. Methods: The current study examined the effect of an acceptance-based behavioral therapy for GAD on the proposed targets for intervention highlighted in several theoretical models: emotion regulation difficulties, intolerance of uncertainty, and low perceptions of control. Clients were randomly assigned to immediate (n=15) or delayed (n=16) treatment. Results: Individuals treated with the acceptance-based behavioral therapy reported significantly fewer difficulties in emotion regulation and fear of emotional responses, as well as greater tolerance of uncertainty and perceived control over anxiety than individuals in the waitlist control condition. In addition, these effects were maintained at 3- and 9-month follow-up assessments. Conclusions: The present study provides promising evidence that an acceptance-based behavioral therapy for GAD has significant effects on the unique targets of intervention highlighted in several prominent theoretical models of GAD. Depression and Anxiety, 2011. © 2010 Wiley-Liss, Inc.