One model of successful time-limited psychotherapy characterizes the therapy as a movement through three interactional stages: the early rapport attainment stage, the middle conflict stage, and the final resolution stage. According to this model, these stages are indicated by the relative presence of communicational harmony. To examine the validity of this model, a study was conducted in which therapist topic determination, defined as the proportion of therapist topic initiation responses that were subsequently followed by the client, was used to represent the degree of communicational harmony. It was hypothesized that successful time-limited therapy dyads would demonstrate a high-low-high sequence of therapist topic determination over the course of treatment while unsuccessful dyads would not. The degree of topic determination over the course of treatment was examined using a replicated N of 1 design for six time-limited psychotherapy dyads, one successful and one unsuccessful dyad from each of the three therapists at a university counseling center. The results indicated that each successful dyad evidenced the general high-low-high pattern of therapist topic determination, but also that there was a fair degree of variation among dyads with respect to the abruptness and speed of moving through the stages. None of the unsucessful dyads were found to have the hypothesized pattern of topic determination. Further research should examine whether this stage model would occur regardless of theoretical approach and whether the same pattern would hold for time-unlimited dyads. (Author/NB)