Teacher retention has been a growing nationwide concern for years that has exponentially worsened as a result of the COVID-19 global pandemic. Schools serving students from low socioeconomic backgrounds tend to be most negatively affected by high rates of teacher turnover. This study examined the impact of implementing effective onboarding on beginning teachers and new hires in a Title I elementary school in an effort to reduce teacher turnover. A mixed methods action research design was utilized whereby an onboarding program was implemented across three phases of improvement using the Plan, Do, Study, Act model. Data were collected using surveys and interviews with the teacher participants. Teacher preparation, teacher retention, benefits and compensation, mentor support, onboarding, and self-efficacy were factors analyzed. Teacher and staff turnover continued to occur throughout each phase of the study. The findings indicate that while the onboarding program implemented had a positive effect on the participants, the results were inconclusive overall due to the numerous confounding variables that arose and could not be controlled by the scholarly practitioner. [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.]