Objective: Within a mixed methods program of research the present study aimed at expanding knowledge about interactions in the initial therapeutic collaboration by combining focus on client interpersonal style and therapist contribution. Method: The study involves in-depth analyses of therapist-client interactions in the initial two sessions of good and poor outcome therapies. Based on interpersonal theory and previous research, the Inventory of Interpersonal Problems (IIP-64-C) was used to define poor outcome cases, that is, low proactive agency cases. To compare good and poor outcome cases matched on this interpersonal pattern, cases were drawn from two different samples; nine poor outcome cases from a large multi-site outpatient clinic study and nine good outcome cases from a process-outcome study of highly experienced therapists. Results: Qualitative analysis of therapist behaviors resulted in 2 main categories, fostering client's proactive agentic involvement in change work and discouraging client's proactive agentic involvement in change work, 8 categories and 22 sub-categories. Conclusion: The findings revealed distinct and cohesive differences in therapist behaviors between the two outcome groups, and point to the particular therapist role of fostering client agency through engagement in a shared work on change when clients display strong unassertiveness and low readiness for change.
