9 © Te Author(s) 2017 B. Stenfert Kroese et al., Cognitive Behaviour Terapy for People with Intellectual Disabilities, DOI 10.1057/978-1-137-47854-2_2 2 History and Theory [W]e just talk about how to deal with our depression and anxiety and that. But she writes things, and she’s doing the fipcharts. Tat’s quite good that. She writes what you think and how you feel at the time. And how to try and cope with them, then she writes the speech bubbles. It’s quite funny, she’s trying to teach me how to make myself feel better. Te quote above is from a woman who took part in a study about people with intellectual disabilities’ views of Cognitive Behavioural Terapy (CBT) (Pert et al. 2012). It hints at the efort that goes into achieving change and the need to make the process meaningful and engaging. But it also begs the question about the therapist’s starting point and what she is trying to achieve in the session. In this chapter we will outline a brief history of CBT and its use with people who have intellectual disabilities, and introduce some of the key underpinning theories. Like other clinicians, we are only too aware of how challenging it can be to balance the use of theory and technique, whilst remaining fexible enough to properly acknowledge the particular needs and concerns of the people with intellectual disabilities we are working with. Tere is also a risk some practitioners will take the view that theory is less important