Almost since its inception, the behavior therapy movement has defined
itself in terms of advancement. Advancement, in turn, implies progress
or moving forward, not stagnation, or regress and moving backward. Ov
er the last 30 years, behavior therapy has witnessed notable advanceme
nts, but also periods of stagnation, and at times regress. The challen
ge of advancement entails progress both from within behavior therapy a
nd from without. Recent trends within the field suggest more attention
to the latter than the former. Behavior therapy, therefore, is at ris
k of failing to advance as a progressive basic and applied science. Fo
r the science and practice of behavior therapy to be a viable force wi
thin the larger psychological community, health care, and society, it
must revisit its theoretical and basic science foundations and continu
e to move forward from within.