The current study aims to ascertain the trajectories of psychotherapy clients' symptom change and identify client factors that predict treatment outcome. We conducted a latent growth mixture model (LGMM) to identify the change trajectories of 44 clients' depression scores during psychotherapy. Client characteristics were then explored to determine whether any were associated with change trajectories. We examined whether the number of physician visits and/or client self-concealment scores predict 63 clients' improvement after controlling for initial symptom severity. Two trajectories of clients' symptom change were identified: nonimprovers (52.3%) and improvers (47.7%). Nonimprovers had higher levels of self-concealment and baseline depression than improvers. The number of physician visits was associated with higher depression scores at baseline and greater clinical improvement during psychotherapy. Clients showed distinct trajectories of symptom change in psychotherapy. Early identification of clients at risk for treatment failure may increase the probability of therapeutic success.