Introduction: How can research discover how to do psychotherapy?

It is almost exceptional that psychotherapy researchers set out to answer questions like these: What are some new and better ways of doing actual in-session psychotherapeutic work? What are some new and better changes that psychotherapy can help bring about, and what are some new and better ways of helping to bring them about? The purpose of this special series of papers is to provide a forum for researchers to tell how to do research to answer those questions, i.e., to present practical and useful methodologies, designs, and strategies that are helpful in answering these questions.