The field of couple and family therapy and, more generally, the field of psychotherapy contain an overwhelming plethora of information about human functioning, problem solving, therapeutic principles, clinical models, evidenced-based treatments, common factors, and established clinical competencies. Therapists face the daunting challenge of determining how to effectively utilize these ideas, models, and techniques. They do so in the face of client systems presenting with a variety of co-occurring problems maintained by factors ranging from a simple lack of information to complex and challenging networks of constraints. Therapists struggle with how best to utilize the available treatments, interventions, and knowledge, as well as how to organize and sequence therapy. Therapists who practice within a particular model struggle with what to do when the strategies and techniques of that model fail to produce the desired change. More eclectic therapists struggle to find a coherent way to organize their work—a set of principles to help them decide what to do and when to do it.