This sequential mixed-method study aimed to explore elementary reading teachers' perceptions and experiences of vocabulary practice and student self-efficacy to increase reading achievement. The quantitative approach utilized a Likert-type survey design shared with respondents through email to identify teachers' perceptions of vocabulary instruction based on their years of teaching experience. Two teachers with one teacher per interview were utilized to address the two qualitative research questions. The findings suggest no significance between teachers' perceptions of vocabulary practice based on their years of teaching experience. Teachers believed that vocabulary practice and self-efficacy are essential factors in increasing students' reading levels. Themes emerged throughout the two interviews to address the two qualitative research questions. [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.]