The purpose of this study was to gain a better understanding of beginning teacher self-efficacy when working with English language learners (ELLs) in mainstream elementary classrooms. Elementary teachers provide instruction for their students during the majority of the instructional day, and supporting students learning a new language while simultaneously learning academic concepts can be challenging. The study sought to identify in-service professional development or training beginning teachers deemed beneficial to their perceived ability to work with ELLs as well as the training or professional development they would like to receive going forward. This mixed methods study was carried out using a survey and focus group interviews. The survey contained the Culturally Responsive Teaching Self-Efficacy Scale and three open-ended questions. Participants were elementary teachers with less than 4 full years of teaching experience who were currently working with students identified as ELLs. The data from the survey were analyzed to determine the mean, mode, and outliers. The data from the open-ended questions and focus group interviews were coded for themes. Findings from the study showed beginning teachers need additional training to effectively work with ELLs. The teachers would benefit from training on Sheltered Instruction Observation Protocols and culturally responsive teaching practices. The teachers could also benefit from observing peers who effectively work with ELLs as well as having someone model effective ELL strategies in their classrooms. The findings from this study can be used to help building administrators and school districts design professional development to support beginning teachers when working with ELLs. [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.]