This study aims to identify factors contributing to linguistic insecurity and provides suggestions to support teachers in fostering linguistic security in their classrooms. The findings are based on data from interviews with 21 high school teachers from across the province of British Columbia (Canada) and a focus group with eight members of the Linguistic Security Committee. A thematic analysis of the data led to the identification of five sets of teacher beliefs associated with challenges about the fostering of linguistic security in their classrooms. For each of these challenges, the Linguistic Security Committee made recommendations, and these may prove helpful to teachers in French-speaking minority contexts across Canada. Three main conclusions are drawn from this study: attention to teacher beliefs should be a focus of educational research, teacher preparation grounded in a sociolinguistic understanding of linguistic variation is necessary, and linguistic security should be a priority.