There is widespread agreement among researchers and educators that teachers contribute to student learning (Darling-Hammond, 2002; Darling-Hammond; 2005; Ferguson, 1998; Goldhaber, 2003; Palardy and Rumberger, 2008; Rivkin, Hanushek, and Kain, 2005; Wright, Horn, and Sanders, 1997). In the face of teacher shortages and turnover, especially in hard to staff schools and subjects, federal and state policies have sought to attract and retain qualified teachers. Some turnover, from a perspective of organizational theory, is often characterized as expected and "healthy." Nonetheless, education has long been viewed as an occupation that depends heavily on cohesion within schools, a cohesion that is disrupted by turnover (Ingersoll, 2001; Lortie, 1975). Further, research has documented that teacher turnover occurs at higher rates in the early stages of their careers (Boe, Cook, & Sunderland, 2006). The purpose of this dissertation is to examine transitions into and out of teaching, longitudinally, among a cohort of college graduates in the early stages of their careers. Using a nationally representative sample of college graduates from the class of 1992-93, I first investigate the entrance of college graduates into teaching. Next, I examine the extent to which teachers change teaching jobs or leave teaching over a ten year period. Finally, I conduct a comparative analysis of teacher leavings relative to those of graduates employed in other occupations. Findings suggest that those graduates who are early entrants into teaching following degree attainment differ from delayed entrants into teaching in important ways. Moreover, the patterns of turnover among teachers who have entered at various times differ. For example, early entrants are more likely to stay in teaching over the course of the early part of their careers. Analyses that compare rates of teacher leavings to rates in other occupations indicate that from 1994 to 2003 teacher leaving rates are greater than in some occupations, such as engineers, pharmacists, physical therapists and nurses, and lower than others, such as secretaries and childcare workers. Overall, findings suggest that policy prescriptions to mitigate undesirable turnover should be differentiated and that a one-size fits all policy is not likely to be effective. [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.]