This study examined the association between therapist interventions, including interpretations, and patient defensive functioning. The first session of 32 (n = 32) Brief Psychodynamic Interventions were rated for therapist interventions and patient defensive functioning. Lag sequential analysis was used to determine if (a) there are organized sequences of therapist interventions; (b) there are predictable sequences in the patients' level of defensive functioning; (c) there are sequences of therapist interventions leading to change in the patients' defensive functioning; and (d) there are levels of patient defensive functioning leading to organized therapist response. Results suggested that there are organized sequences in the therapists' interventions and that patient in-session defensive functioning is relatively stable. However, no chain of therapist interventions led to a predictable response in the patients' defensive functioning or vice versa.