The proposed mechanism of action in Functional Analytic Psychotherapy (FAP) is therapist-contingent responses to client in-session behavior that parallels out-of-session problematic behavior. In theory, these responses shape adaptive behaviors that generalize into the client's daily life (Tsai et al., 2009). Therefore, the therapist's response repertoire must be ripe with interpersonally effective responses to model and shape client behavior. Thus, trainings in FAP were designed not only to equip therapists with a skillset in implementing the fundamentals of shaping but also to serve several other functions, including facilitating the development of an effective interpersonal repertoire to promote shaping. Kanter, Tsai, Holman, and Koerner (2013) demonstrated that 8-week FAP trainings may increase knowledge of FAP principles as measured through self-report and analogue tasks; however, no research examines reported changes in therapists' interpersonal behavior in or out of session. We believe that an 8-week FAP training will increase therapist use of effective interpersonal behavior (tCRB2) and decrease therapist maladaptive behavior (tCRB1). Four newly graduated and graduatelevel therapists attended an 8-week FAP training. Using an AB single-subject design, we examined the frequency of targeted interpersonal behavior. Results indicated that FAP trainings may have an impact on therapists' daily life behaviors as demonstrated through changes in weekly frequency counts. Although the design includes significant limitations (see Discussion), these data provide some support for the utility of 1 theorized function of FAP trainings.