“…Even though individual therapy may be more efficient in addressing specific needs of each patient, group treatment settings tend to offer more opportunities for universality-by recognizing common experiences among group members-and normalization (Manassis et al, 2002;Wergeland et al, 2014), both of which are acceptance-related processes. Furthermore, some studies indicate that group CBT can be as effective as individual CBT for anxietyrelated disorders (Oie & Boschen, 2009;Pozza & Dèttore, 2017;Sharp, Power, & Swanson, 2004;van Ingen & Novicki, 2009). Other CBT and mindfulness/acceptance-based approaches for GAD have been tested using a group format in several clinical trials (Avdagic, Morrissey, & Boschen, 2014;Craigie, Rees, Marsh, & Nathan, 2008;Dugas et al, 2003;Evans et al, 2008;McEvoy et al, 2015;Stanley, Beck, & Glassco, 1996;Wetherell, Gatz, & Craske, 2003;Wong et al, 2016), most of them showing large effect sizes for the reduction of anxiety and worry.…”