Scientific models are like tools, and like any tool they can be evaluated according to how well they achieve the chosen goals of the task at hand. In the science of treatment development for chronic pain, we might say that a good model ought to achieve at least 3 goals: 1) integrate current knowledge, 2) organize research and treatment development activities, and 3) create progress. In the current review, we examine models underlying current cognitive behavioral approaches to chronic pain with respect to these criteria. A relatively new model is also presented as an option, and some of its features examined. This model is called the psychological flexibility model. This model fully integrates cognitive and behavioral principles and includes a process-oriented approach of treatment development. So far it appears capable of generating treatment applications that range widely with regard to conditions targeted and modes of delivery and that are increasingly supported by evidence. It has led to the generation of innovative experiential, relationship-based, and intensive treatment methods. The scientific strategy associated with this model seeks to find limitations in current models and to update them. It is assumed within this strategy that all current treatment approaches will one day appear lacking and will change.