The purpose of the current study was to investigate if high schools in an innovative school model in the United States adhere to the mission of the model over time or if they drift away from their mission. The innovative school model asks its school to make commitments to design aspects that help determine the power structures in the school, the Project Based Learning pedagogy employed, the use of instructional technology, and the outcomes that are guaranteed for the students. The phenomena of mission drift and adherence were examined, as well as the relationship that leadership has to contributing to these patterns in the innovative school model. Various factors were explored that contribute to patterns of either mission adherence or drift in the innovative school model: principal hiring and succession, supports for campuses from their district or the national organization, and systems and processes that exist in the school. These factors were explored through an evaluation of historical survey data at the schools and through interviews of current innovative school model principals. The findings of the qualitative study and the quantitative study reaffirmed each other. It was found that innovative model schools are successful at fulfilling the mission of the model, even after the schools mature past their initial implementation contract. Having clearly codified commitment criteria, surveys to gauge success, a coaching model, and other structures helped to tether innovative model schools to the larger national organization and to long-term mission adherence. [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.]