in the 1950s and the establishment of classical CBT, when cognitive and behavioral approaches were combined. The third wave took place in the 1980s and 1990s, when principles originating from Buddhism, especially mindfulness and acceptance, significantly contributed to the development of various new forms of CBT. Over time, cognitive behavior therapy became an umbrella term for all cognitive-based psychotherapies.

CBT is a "problem-focused" and "action-oriented" form of therapy. The therapist's role