The Research and Teaching Fellowship (RTF) of the University of Maryland Libraries in College Park is a three-semester teacher training program for students seeking a master's of library and information science (MLIS) degree. This article provides details of the program's content, organization, administration, and assessment. It also includes results from a mixed methods and longitudinal study identifying the successful components of RTF and charting the development of teacher efficacy and identity among participants. Findings indicate that a strong sense of community, sustained engagement with teaching, and the integration of evidenced-based practice prepare MLIS students to succeed in a competitive job market. The authors provide a list of best practices in the development of mentorship and training programs, including considerations for librarians and administrators