Anxiety disorders are among the most prevalent mental disorders, and women are at much higher risk to develop an(y) anxiety disorder. Women seem to experience more severe and long-lasting symptoms than men. Sex differences regarding etiology can be best understood from a vulnerability-stress perspective. A different exposure to psychosocial stressors and an increased biologic and/or psychologic vulnerability toward anxiety in women may contribute to the sex differences in anxiety disorders. Evidently, these findings have implications for both the diagnosis and treatment of patients with anxiety disorders. Therapists should be aware of gender bias during the diagnostic process and be sensitive for self-reporting bias (i.e., the reluctance to report “female-like” symptoms by men). Research on sex differences with respect to treatment is lacking and gender-related knowledge has rarely been integrated into clinical interventions. Interventions aimed at transdiagnostic factors that have been shown to relate to sex differences in anxiety seem rather promising and have the potential to enhance the care for both men and women with anxiety disorders.