Out-of-field teaching is a national occurrence that has not had extensive examination in relation to teacher retention and attrition. Using a nationally representative sample of secondary public school teachers, (N=770) taken from the 2003-2004 Schools and Staffing Survey (SASS) and the 2004-2005 Teacher Follow-up Survey (TFS) datasets, the current study analyzed whether and why out-of-field teachers were more likely to leave their teaching positions or professions. Results revealed that out-of-field teachers were more likely to leave the teaching profession. Results also revealed that teachers with higher levels of self-efficacy had positive direct and indirect effects on teachers that stayed in their schools and profession. The results of this study could provide valuable information for policy makers and administrators to increase teacher retention and understand the additional consequences out-of-field teaching has on their schools.