Abstract: The primary purpose of this study was to develop and validate an instrument designed to determine the extent of secondary school racial integration using the School Climate and Integration Questionnaire for Students as the criterion measure. A secondary purpose was to determine the extent of integration in the schools used for validation. A review of literature was completed and an instrument, entitled the Instrumentation for the Assessment of a School's Strengths and Weaknesses in Integration, was constructed and validated. The instrument provided a means for practitioners to examine the status of a secondary school on various sensitive indicators of integration. The items which were included in the instrument were selected as a result of what experts, familiar with the desegregation-integration continuum, recommended as indices of integrated schools. Content validity of the instrument was established by ratings made by directors of the federal desegregation center for race on each item of the instrument. Sixteen factors and practices were found to be related to school integration, including: 1. The extent to which a school's curriculum dealt with the history, culture, and contributions of minorities to American society. 2. The ethnic composition of a school's staff and student population. 3. The school's disciplinary practices and procedures. 4. The distribution, by ethnic group, of students enrolled in college preparatory or special education classes. 5. The participation of minority students in school extracurricular activities. 6. The student friendship patterns found in the school. A comparison was made between the instrument developed in the study and the School Climate and Integration Instrument Questionnaire for Students, a criterion measure that had been previously validated. The purpose of this comparison was to determine if similarities existed between the specific integration characteristics measured by each instrument. Seven comparable school integration characteristics were found to be present. The two instrument were then used to determine the extent of integration found in two Florida high schools. The finding were comparable. Based on the results of this study, it was concluded that the developed instrument, Instrumentation for the Assessment of a School's Strengths and Weaknesses in Integration, can be used by practicing school leaders to measure a school's integration status. Dissertation Discovery Company and University of Florida are dedicated to making scholarly works more discoverable and accessible throughout the world. This dissertation, "The Development and Validation of an Instrument to Determine the Extent of Secondary School Integration" by John Walter Beall, was obtained from University of Florida and is being sold with permission from the author. A digital copy of this work may also be found in the university's institutional repository, IR@UF. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation.