Cognitive-behavioral therapy (CBT) has been found to be effective in the treatment of anxiety disorders such as obsessive-compulsive disorder (OCD) and posttraumatic stress disorder (PTSD). There is a gap, however, between reports of controlled clinical trials and actual clinical use of the methods of CBT in general medical and psychiatric settings. While psychiatric medications are commonly the first line of treatment, pharmacotherapy may not completely eradicate symptomatology or may have a delayed effectiveness, during which time patients continue to suffer. Cognitive and behavioral interventions can complement, if not replace, pharmacotherapy for relief of symptoms of OCD and PTSD. This article explains how CBT works in the treatment of OCD and PTSD. Basic instructions for implementing these treatment methods are provided.