INTRODUCTIONThe three-channel hypothesis (Russell & Stiles, 1979) distinguishes three classes of verbal process-coding categories and proposes that each class taps a different channel of interpersonal communication in psychotherapy. Content categories, such as body parts or separation anxiety, concern denotative or connotative meaning of discourse units. The content channel carries information about the speaker's current concerns, attitudes, and personality dynamics. Extralinguistic categories, such as laughter or hesitation, concern speaking behaviors that accompany or modify language, but are themselves neither semantic nor syntactic. The extralinguistic channel carries information about the speaker's current (and usually transitory) emotional state-a momentary state of anger, for example, in contrast to an enduring attitude of hostility toward someone. Intersubjective categories, such as question or blame, concern brief relationships of the speaker to the intended recipient; that is, unlike content or extralinguistic categories, intersubjective categories imply the existence of another person (e.g., one questions another person; one blames another person). The intersubjective channel carries information about interpersonal relationships and social roles, and, in psychotherapeutic communication, about the therapist's technique.The three-channel hypothesis does not require that any type of information be carried exclusively in one channel (nor are these three an exhaustive listing of possible channels). For example, information about