The purpose of this study was to identify Nebraska principal perceptions regarding the level of participation the AdvancED school improvement process. Further, the study identified differences among principals' knowledge, based on demographic characteristics of years of experience, size of school enrollments, and formal training in school improvement and external review team participation and leadership. The study identified which demographic factors exhibited the greatest effect upon the Nebraska principals' participation levels as they pertained to school improvement process. Surveys were distributed to 142 Nebraska principals. The web-based survey consisted of twenty-seven questions regarding the perceptions of principal participation about school improvement practices. The first nineteen questions of the survey related directly to the seven phases of the school improvement process. In addition the survey contained two questions in which respondents rank ordered priorities in terms of principal roles within a district and rank ordered principal involvement in the phases of the school improvement process. The survey also collected additional information concerning the participants: their formal training with regard to school improvement process, their number of years of experience as an administrator, their number of years of experience in education, participation on External Review Teams, participation as External Team Leader, and current district enrollment for the current school year. The statistical analysis indicated that principals should attend formal training opportunities in school improvement provided by a regional accreditation institution or the Nebraska Department of Education. The study also suggested that principals should have training in the specific components of governance, policies, and leadership processes, which thereby enhance the knowledge of daily school improvement practices for the principal. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]