School districts seek to increase teacher retention in response to nationwide teacher shortages. The problem is that teachers who have taught for 5 years or less have the highest attrition rates compared to other teachers, with more than 44% of new teachers leaving the profession within the first 5 years. The purpose of this qualitative case study was to explore the experiences of second-career K-5 teachers in Florida who have taught for 5 years or less. Self-determination theory was the theoretical framework for the study, advancing the idea that autonomy, competence, and relatedness support second-career teachers' intrinsic motivation and social integration. Three research questions targeted the initial experiences of second-career teachers (SCTs) and the instructional coaches who provide training and support to SCTs. The sample consisted of 16 SCTs and five Instructional coaches selected through purposive sampling from eight Florida schools. Data from the questionnaire, interviews, and the focus group were examined using Braun and Clarke's thematic analysis. Results revealed that SCTs experience fulfillment while facing unrealistic expectations and perceive teaching as a worthwhile career with an unattainable work-life balance, while the instructional coaches acknowledged challenges in SCTs' support. Recommendations include increasing stakeholders' awareness of SCTs' characteristics and needs, implementing training and support to highlight SCTs' existing skills and target the pedagogical gaps, and improving communication and collaboration to match SCTs' needs for relatedness, autonomy, and competence. The study's results may benefit education stakeholders seeking to understand and respond to the SCTs' needs and increase their employment stability. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]