Previous research has supported the immediate activation of patients' strengths (resource activation) as an important change mechanism in psychotherapy. Two different studies of integrative cognitive-behavioral therapy (CBT) treatments demonstrated that fostered strengths-oriented CBT treatments were more effective than the control conditions. Within these two studies, the authors tested the effect of specific resource-activating strategies at the beginning of therapy (Sessions 2, 5, and 8) using a pairwise matched control group design. The in-session processes were measured by video observer ratings (N=96 sessions). Results indicate that in the strengths-fostering treatments therapists and patients focus more strongly on patient competencies and personal goals in comparison to the control groups. These in-session processes have a direct impact on session outcome (particularly self-esteem, mastery, and clarification experiences). Results are discussed in regard to actively implementing resource-activating behavior as superordinate principles of change and their relevance for therapy outcome.