School district administrators implement 1:1 programs into classrooms with the expectation to enhance students' academic abilities and promote 21st-century skills. The problem was pre-K-12 teachers' perceptions, practices, and professional development with the newly implemented 1:1 laptop device remained a fertile area of study. Utilizing teachers' voices in the implementation process of a 1:1 program was vital, as teachers are leading educational stakeholders integrating the devices into classroom instructions. A profusion of literature emphasized the positive impact of 1:1 technology usage in classrooms and educational stakeholders' views, but a gap in the literature concerning the paucity of research remained about teachers' voices in 1:1 programs. The theory of planned behavior (TPB) was the applied theoretical framework for this study. Using the TPB, administrators may obtain answers about teachers' perspectives, practices, professional training, and how 1:1 laptops are integrated into classroom instructions to promote students' success. The purpose of this qualitative instrumental case study was to explore pre-K-12 teachers' perceptions, practices, and professional development with newly implemented 1:1 laptop devices. A need for an exploration of how teachers' voices in a newly implemented 1:1 program can promote 1:1 program success prompted the study. A purposeful sampling of 14 certified teachers aided in data collection through an open-ended questionnaire, focus group, and individual face-to-face interviews. Data analysis utilized the content analysis approach to understand the data through coding and recognizing themes. Results from the study revealed teachers accepted 1:1 technologies in classrooms as necessary tools for enhancing students' academic abilities. Teachers utilized 1:1 laptop devices in different ways and expressed a need for teachers' voices, ongoing professional development, quality devices, and experienced technology support personals for the success of the implementation. [This book was edited by Ismail Sahin and Wilfried Admiraal.]