Coherence therapy is a system of psychotherapy based in the theory that symptoms of mood, thought and behavior are produced coherently according to the person's current mental models of reality, most of which are implicit and unconscious. It was founded by Bruce Ecker and Laurel Hulley in the 1990s. It has been considered among the most well respected postmodern/constructivist therapies. General description The basis of coherence therapy is the principle of symptom coherence. This is the view that any response of the brain–mind–body system is an expression of coherent personal constructs (or schemas), which are nonverbal, emotional, perceptual and somatic knowings, not verbal-cognitive propositions. A therapy client's presenting symptoms are understood as an activation and enactment of specific constructs. The principle of symptom coherence can be found in varying degrees, explicitly or implicitly, in the writings of a number of historical psychotherapy theorists, including Sigmund Freud (1923), Harry Stack Sullivan (1948), Carl Jung (1964), R. D. Laing (1967), Gregory Bateson (1972), Virginia Satir (1972), Paul Watzlawick (1974), Eugene Gendlin (1982), Vittorio Guidano & Giovanni Liotti (1983), Les Greenberg (1993), Bessel van der Kolk (1994), Robert Kegan & Lisa Lahey (2001), Sue Johnson (2004), and others. The principle of symptom coherence maintains that an individual's seemingly irrational, out-of-control symptoms are actually sensible, cogent, orderly expressions of the person's existing constructions of self and world, rather than a disorder or pathology. Even a person's psychological resistance to change is seen as a result of the coherence of the person's mental constructions. Thus, coherence therapy, like some other postmodern therapies, approaches a person's resistance to change as an ally in psychotherapy and not an enemy. Coherence therapy is considered a type of psychological constructivism. It differs from some other forms of constructivism in that the principle of symptom coherence is fully explicit and rigorously operationalized, guiding and informing the entire methodology. The process of coherence therapy is experiential rather than analytic, and in this regard is similar to Gestalt therapy, Focusing or Hakomi. The aim is for the client to come into direct, emotional experience of the unconscious personal constructs (akin to complexes or ego-states) which produce an unwanted symptom and to undergo a natural process of revising or dissolving these constructs, thereby eliminating the symptom. Practitioners claim that the entire process often requires a dozen sessions or less, although it can take longer when the meanings and emotions underlying the symptom are