Nomophobia is "the fear of being unable to use one's mobile phone or being unreachable through one's mobile phone" (Yildirim & Correia, 2015, p. 1323). A sample of 161 professional teachers from accredited private schools in Kansas and Missouri was utilized to measure levels of nomophobia and differences based on teachers' gender, age group, and grade level taught. The survey data was collected using the Nomophobia Questionnaire (NMP-Q) created by Yildirim (2014). Independent-samples t tests and ANOVAs were used to address the four research questions. Results indicated that teachers are experiencing moderate to severe nomophobia. Additionally, female teachers' levels are higher than male teachers, teachers 18-35 have the highest level of all of the age groups, and teachers in early education and elementary schools experience higher levels of nomophobia. Further analysis regarding the four underlying factors of nomophobia revealed significant levels of nomophobia in the fear of being unable to communicate, the fear of losing connectedness, and the fear of being unable to access information. Female teachers reported significantly higher levels of nomophobia in the fear of losing connectedness, the fear of being unable to access information, and the fear of losing convenience. Also, teachers between the ages of 18 and 35 reported significantly higher levels of nomophobia in the fear of losing connectedness, the fear of being unable to access information, and the fear of losing convenience. Early childhood and elementary teachers reported significantly higher levels of nomophobia for all four subfactors. As one of the first to measure teachers' nomophobia, this study raises awareness of concerns within classrooms and the need to create well-informed policies and procedures emphasizing a healthy balance of technology usage at school. [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://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]