The influence of counselor and client sex on relational communication patterns in counseling was studied within a systems theory framework. Seventytwo audiotaped intake interviews of 36 counselors, each of whom interacted with one male and one female client, were analyzed by the Relational Communication Coding System (Rogers & Parace, 1975). This system operationalizes the constructs of complementarity and symmetry. Transactions involving male clients were characterized by more complementary exchanges in which the use of questions and the provisions of answers provided a basis for attempts to assert or relinquish control in the relationship. Female clients and counselors were found to share more neutral messages in which the issue of control was less salient. Both counselor sex and client sex were significant factors in participants' perceptions of each other during the intake.Although the counseling process has long been acknowledged as an interactional one that emphasizes power and influence as reciprocal exchanges (Danziger, 1976;Jackson & Haley, 1968;Strong & Claiborn, 1982), most empirical investigations of this process have taken the individual as the basic unit of analysis. This focus has endured despite the development of several complex theoretical perspectives that describe transactional patterns in counseling settings. One particularly influential concern of systems theorists (e.g., Haley, 1976;Watzlawick & Weakland, 1977) centers on how verbal communication is used by participants in counseling to define their relative power and control.Key constructs in this area are the notions of complementarity, or relationships in which participants have unequal control (i.e., one assumes a one-up position and the other This research was conducted as part of the doctoral dissertation of the first author submitted to the Psychology Department at the University of Connecticut under the direction of the second author.The authors thank David A. Kenny and Julian B. Rotter for their helpful comments regarding the design and implementation of the study. The authors also thank Jack Davis for statistical consultation and Patty O'Brien for 'her help in scoring the audiotaped interviews.