Instructors in the federally funded program of Language Instruction for Newcomers to Canada (LINC) are responsible for teaching both the English language and citizenship values to adult immigrants. The recent legalization of same-sex marriage implies that a gay and lesbian presence is an acknowledged fact of Canadian life, with gay rights now entrenched in the value system. This context led to questions of "if", "how", and "why" teachers do or do not address sexual diversity in the classroom. A preliminary study utilizing a survey questionnaire and semi-structured interview was carried out with Alberta LINC teachers to explore perceptions of sexual diversity in relation to their teaching. Results indicate that the learning environment is characterized by the invisibility of the issue. Various redresses are suggested: teachers can utilize an inquiry approach to identity and learner autonomy; publishers can produce materials that include sexual diversity; and teacher-training programs can revise syllabi and teaching approaches in core TESL classes. (Contains 1 note and 3 tables.)