The aging population is a worldwide phenomenon. An increasing number of older adults are interested in learning languages but they often become disheartened because of strict rules imposed on them by language teachers blindly following the trend of “foreign language only.” For many decades following the end of Grammar Translation method, students’ mother tongue has been banned from language classrooms. Fortunately, however, this trend is beginning to shift giving place to more lenient approaches to teaching based on allowing and encouraging own-language use. Indeed, recent studies prove that there are a number of advantages resulting from permitting the use of translation, whereas it seems that there are hardly any real obstacles besides the ones existing as part of teachers’ own beliefs. Adults are not a homogeneous group and yet it is rarely acknowledged in studies on the use of mother tongue in language classrooms. As in case of any other age group, younger and older adults’ abilities, needs and learning preferences should also be taken into account to make their learning process more effective and more suitable. The aim of this article is to provide a foundation for future research on the adult learners and the use of their mother tongue in the classroom environment.