Ninety-two individuals diagnosed with GAD were randomized to receive 10 sessions of either an acceptance-based behavior therapy (ABBT) or a Non-directive support Therapy (NDST). Assessments were at pretreatment, mid term, post-treatment, and 3-month follow-up.Data were analyzed using the Mixed effect regression models comparing both groups in primary outcome measures. Secondary outcome measures and putative process variables were assessed and also analyzed. The latter were tested as mediators of efficacy.