From Marsha Linehan article on everything2:
Dr. Linehan’s education was based in the established field of cognitive-behavioral psychology, which the video refers to as `a technology of change’, focused on changing behavior through learning and experience. However, while treating borderlines in the early 1980s, Dr. Linehan decided that the cognitive-behavioral model that she was working with was insufficient, and that she needed to incorporate an element she calls `radical acceptance’. Dr. Linehan makes clear in her videotaped presentation that `acceptance’ was a real buzzword in psychology around the time that she started to promote DBT, but she maintains that her idea of `radical acceptance’ is different. When most psychologists talk about `acceptance’, she states, they mean `acceptance as change’, accepting the client in order to create a change, accepting the client’s unfulfilled potential instead of the client’s actual being. Dr. Linehan believed that for her borderline clients to get well, therapy needed to involved a level of acceptance that would go above and beyond `acceptance as change’. For inspiration, she turned to Eastern psychology as translated into Zen Buddhist meditation practice. However, fearing that her colleagues due to their cultural biases would not take her work seriously if she were to call it `Zen Behavior Therapy’, Dr. Linehan also researched Western philosophical traditions. There she discovered dialectics, the approach in which thesis paired with antithesis brings synthesis. Dialectics seemed appropriately seasoned for the Western palates of the practitioners who would be reading her work, and thus, DBT was born.