Anxiety disorders are one of the disorders most frequently requested for psychological attention. The purpose of this study is to identify the factors that can explain a longer duration of psychological treatment for anxiety disorders. Method: 202 patients from the University Psychology Clinic of the Complutense University of Madrid were analyzed. Results: Multivariate regression analysis showed that the presence of obsessive-compulsive disorder and the application of arousal control techniques followed by modeling and other specific techniques were the best predictors of treatment duration. Conclusion: Reducing as much as possible the number of techniques applied without reducing intervention efficacy is suggested. In some disorders that produce a greater life disorganization, it may be useful to try to organize the patient´s life either as a first goal or at the same time as the intervention program, so as to increase its effectiveness and reduce the number of sessions
