National attention is focused on the state of science, technology, engineering, and mathematics (STEM) education in public schools. In order to ensure that students have access to high quality STEM education it is essential that teacher candidates are well prepared and confident to deliver challenging content and train students in necessary skills for future career opportunities. Unfortunately, despite training, many STEM teachers are leaving the profession before retirement. This research study investigates the current practices traditional and alternative preparation programs to determine their effect on self-efficacy, motivation, and desire to remain in the teaching profession. Data were collected through a survey distributed to current Maryland public school teachers and graduates of teacher preparation programs in Maryland. Participants were asked to share the characteristics of their teacher preparation program and rank the overall effectiveness of the program and student teaching experiences. The survey also included the Teacher's Sense of Self-Efficacy Scale, the Work Intrinsic and Extrinsic Motivation Scale, and the T-STEM instrument to assess teacher self-efficacy, motivations, subject matter self-efficacy, and use of STEM teaching practices. Study participants included secondary science, technology, engineering, and math teachers, STEM resource teachers, and elementary STEM teachers (n=628). The study found that teachers generally had positive views of their preparation program and were committed to remaining in the teaching profession. Teachers who ranked their preparation program as effective were more likely to have higher levels of intrinsic motivation and self-efficacy. In addition, the study found a strong relationship between preparation program characteristics and subject matter self-efficacy and current teaching practices. This highlights the value of adequate preparation of teachers for successful careers in the classroom. Overall, this study highlights important best practices to develop well-prepared and effective educators. This study has important implications for teachers, school administrators, program directors, and policy makers. Despite the significant relationships between teacher preparation, self-efficacy, motivation, and teaching practices, there was limited support to show the effect of preparation on retention. Future research should investigate factors that affect long-term STEM teacher retention and seek to understand why teachers leave the teaching profession. [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.]