The efficacy of (cognitive) behavioral therapy ([C]BT) for generalized anxiety disorder was investigated and compared with the efficacy of pharmacological therapy using meta-analytic techniques. A total of 65 (C)BT studies and pharmacological studies were included. (C)BT was more effective than control conditions. The results of the comparison between (C)BT and pharmacotherapy varied according to the meta-analytic methods used. Conclusions about differences in efficacy between therapy approaches are limited when all available studies are included owing to a number of factors that influence effect sizes. When only those studies that directly compared both therapies were included in the analysis, there were no significant differences in efficacy. Attrition rates were lower for (C)BT, indicating that it is better tolerated by patients.