There is a paucity of empirical studies that demonstrate psychotherapy trainees improve at assisting their clients' therapy outcomes over time. We examined whether trainees (i.e., practicum, predoctoral interns, and postdoctoral fellows) improved in their clients' therapy outcomes over time. We examined 114 trainees (i.e., who were trainees for the first client in the database) and had over 12 months of client outcome data (M = 45.31 months). At the start of their time in our database, about half of the participants (48.2%) were predoctoral interns, 42.1% were practicum students, and 9.6% were postdoctoral fellows. Collectively, they treated 2,991 clients (M = 26 clients per trainee). Clients completed the Behavioral Health Measure, which assesses general psychological functioning (i.e., well-being, symptom distress, and life functioning), as a measure of therapy outcomes. Trainees demonstrated small-sized growth in their clients' outcomes over time (d = 0.04 per year); however, this growth was moderated by client severity. That is, trainees demonstrated growth over time in working with clients who were less distressed (d = -0.13 to 0.10 over time), but there was no change over time for trainees when working with more distressed clients (d = 0.67 to .65 over time). The results were consistent across trainee level (i.e., practicum, predoctoral intern, postdoctoral fellow), yet trainees varied in their patterns of growth. Psychotherapy training has a small, but positive, effect on trainees' ability to foster positive outcomes with their clients over time. (PsycINFO Database Record
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