Occupational Therapists (OTs) are tasked with making effective clinical decisions to maximize client outcomes. There is, however, a dearth of evidence regarding if, how, and when changes in clinical decision-making occur during the OT education process. This research report presents the outcomes of a quantitative study examining changes in clinical decision-making from pre-OT education to post-education OT employment. Participants (N = 385) were comprised of five groups: (1) a control group of non-OT students (n = 97); (2) students self-selecting into OT education (n = 64); (3) OT students who completed classwork but not fieldwork (n = 70); (4) students who completed fieldwork but had less than two years of experience (n = 98); and (5) experienced practitioners with greater than five years of experience (n = 56). Outcomes of a six-item survey developed and evaluated by the researcher indicated a progressive increase in clinical decision-making, with significant differences between the non-OT, self-selecting, and classroom groups. No significant differences in performance, however, were identified between the classwork, fieldwork, and experienced groups, indicating a significant increase in decision-making ability achieved by the conclusion of pre-fieldwork education that was maintained into practice. Results indicated pre-OT students enter programs with an already developed level of clinical decision-making relative to their non-OT peers, identifying the importance of careful admission processes. Further, decision-making ability is most impacted during in-class training and is minimally improved by actual practice, highlighting the importance of early exposure to clinical decision-making during in-class training to develop competent decision-making in students. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]