To date, language testing research has devoted little attention to adult L2 learners with low levels of alphabetic print literacy (LESLLA), even though this population makes up for a substantial proportion of the candidature of language tests used for migration purposes. This special issue focuses on LESLLA learners, shows how literacy impacts test performance beyond what might be considered construct relevant, and how a focus on LESLLA learners invites a reconceptualization of commonly held notions of literacy, test misuse and even validation.