Many people have different reasons for seeking CBT out. Some have heard about it from friends; some have been recommended by general practitioners; some have come across it in their reading or on television. It is an extremely popular, modern mode of therapy, and I gained most of my experience practicing it while working for the NHS.
Cognitive Behavioural Therapy shares its core beliefs with philosophies such as Stoicism. It builds upon a library of therapeutic knowledge that can be traced all the way back to the 1920s and the introduction of therapies based around behaviour patterns. In the 1960s this was further developed by combining it with a 'cognitive' therapeutic process, initially developed by practitioners such as Alfred Adler. During the eighties and nineties, this process was further honed; developing the general modes of practice that therapists still currently employ.
Today, CBT has been recognised throughout the world as a valid, helpful and practical tool in treating a range of conditions or disorders. You can find out more about the processes CBT uses and how it works here.