The major theoretical paradigm that informs couple and family therapy is family systems theory (FST). Within the FST framework, there are many concepts and assumptions that provide a lens with which to view the dynamics within a system. Indeed, FST cuts across the major models of therapy practiced by family therapists (e.g., structural family therapy, strategic family therapy, experiential family therapy). Within each of the various models of therapy, however, the way in which the specific FST ideas are conceptualized varies based on the models’ respective core tenets.

At the most basic level, FST emphasizes symptom causality and maintenance, seeing behaviors as a function of the mutually interactive and potentiated connections between an individual and those with whom the individual is affiliated within his or her ...