The Motivation of Teachers to Assume the Role of Cooperating Teacher This study explored a phenomenological understanding of the motivation and influences that cause experienced teachers to assume pedagogical training of student teachers through the role of cooperating teacher. The research question guiding the study was what motivates teachers to assume the role of cooperating teacher. The encompassing motivational and theoretical foundations of this study were Deci and Ryan's (1985, 1991, 2000, 2002) Self-Determination Theory; Deci and Flaste's (1995) supportive needs of mastery and competence; and Ryan, Huta, and Deci's (2008) attribute of generosity as it applied to this study's data analysis. The research strategy and methods employed a qualitative methodology. Research utilized the open-ended responses from a researcher-designed survey, cooperating teacher interviews, and a focus group interview. The goal of the survey was to understand respondents' perspectives and motivations with the intent of developing interview questions for the second phase of the study and identifying potential candidates for interviewing cooperative teachers active in the role during the time-frame of the study (December 2003-July 2004). The second phase of the study was a qualitative investigation regarding the motivation of five cooperating teachers obtained through individual interviews and a focus group interview for the purposes of adding and verifying data collected. This completed triangulation of the data. For the purposes of understanding the perceptions of the participants' lived experiences (Smith, 2003), the research utilized a phenomenological approach. The triangulated data from the open-ended survey questions, the individual interviews, and the focus group's combined indicated general motivators for serving as a cooperating teacher. Mastery through reinforcement of existing skills appeared as the primary motivator, although mastery through increasing knowledge base was virtually equal in its representation. Generosity towards others was the secondary motivator. Collectivism was the third motivator. The primary extrinsic motivation included elimination of teacher isolation. Educational culture/climate as perceived disillusionment with administration, college, or university system through lack of autonomy surfaced as the primary motivator for serving as a cooperating teacher. The significance and implications of the research leads to scholarship of integration, not only at the post-secondary level, but also by those affiliated with recommending teachers to serve as cooperating teachers and those who work with cooperating teachers during the field experience. This may result in re-evaluating and creating new courses and curricular advancements (Boyer, 1990) at the post-secondary levels. As intrinsic motivation is a lifelong aspect (Ryan, personal communication, November 11, 2005), so must those who work with teachers who assume the role of cooperating teacher understand that impetus. When establishing a sense of camaraderie with university or college personnel, facilitated leadership emerges (Dantonio, 1995). [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.]