The purpose of this study was to examine the ongoing issue of teachers with chronic absenteeism particularly as it relates to vulnerable student populations. For the purposes of this research, chronic absenteeism is defined as missing 10 or more instructional days. The problem is the effect that chronic teacher absenteeism has on vulnerable student subgroups, which is not clear in the empirical literature. Through the research process, the outcomes attempted to provide an answer to the following question: How does teacher absenteeism impact student achievement scores for English learners (ELs), students with disabilities, and students from low socioeconomic backgrounds? During this study, a quantitative causal-correlation design was used to determine the influence chronically absent teachers have on academic outcomes of students with disabilities, ELs, and students who live in poverty in a school district in southwest Florida. District and state assessment data of students were collected and analyzed by those students assigned to teachers with 10 or more days of personal or sick leave. Each of the teachers included in the study had at least five students enrolled in their classrooms who identify as a student with a disability, ELs, or a student living in poverty. The overall findings revealed no significance on the students' performance based on the teacher's attendance; however, the findings do have implications that can be used to inform school administrators and education policymakers about the impact teacher absenteeism may have on academic outcomes for vulnerable student populations. [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.]