Cognitive behavior therapy (CBT) is a structured short-term therapy designed to change the patient's negatively distorted cognition. The effectiveness of cognitive therapy/cognitive behavior therapy has been increasingly recognized not only by professionals and academics but also by the public, and in April, 2010, this therapy started to be covered by the national health insurance in Japan. In this article, the author described the high-intensity and low-intensity CBT from the practical point of view.