This study explored and compared the ways in which school-based cooperating teachers and college supervisors evaluate student teachers. The scores allocated to student teachers by school-based cooperating teachers and college supervisors in the final field experience evaluations of student teachers were analyzed. A mixed methods research design was used to gather information. Quantitative data from the student teacher field experience evaluation forms were analyzed using a paired t-test (alpha 0.01) to compare the mean scores allocated by college supervisors and school-based cooperating teachers and college supervisors and college special methods supervisors. The instrument measured seven different categories: Critical thinking; human relations; assessment; communications; leadership; methods; and professionalism. When comparing the mean scores allocated by the three groups of supervisors, the overall trend showed cooperating teachers allocated higher scores than college supervisors, with one small exception: at the secondary level, the mean score of college special methods supervisors for the category "leadership" was very slightly higher (not significant) than that of cooperating teachers. Significant differences were found in several categories: between elementary cooperating teachers and college supervisors; secondary cooperating teachers and college supervisors; and secondary cooperating teachers and secondary special methods supervisors. College supervisors' and special methods supervisors' mean scores were very similar, with no significant differences occurring in any of the categories. To explore reasons for these differences, qualitative data were collected through focus group interviews with three elementary school-based cooperating teachers, three secondary school-based cooperating teachers, three college supervisors, and three college special methods supervisors. Findings included: Interpretation of the instrument scale was subjective; supervisors did not all use the same indicators in the categories; cooperating teachers spend much more time with student teachers than did college-based supervisors and so had a more holistic view of student teachers' performance; the relationships formed between cooperating teachers and student teachers may impact the score allocated on the instrument. Recommendations from the study include improving the validity of the student teacher evaluation instrument and providing training to all supervisors in the use of the instrument to increase inter-rater reliability among supervisors. [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.]