This collection makes the case for exploring individual differences (IDs) in foreign language reading, arguing for a shift from a universalist view toconsider new ID-focused theories and methodologies. The volume demonstrates the need to recognize individual variations, such as lexical knowledge and working memory capacity, and the diverse cognitive and linguistic profiles of learners in the study of reading, particularly in mixed-ability learning environments. The chapters explore variability among learners and their impact on reading dynamics, acquisition, and instructional effectiveness. Seeking to bridge theory and practice, the collection empowers stakeholders with a better understanding of the theoretical foundations of the intersection of ID research and reading practices toward effective practical implementation in the classroom. This book will appeal to students and scholars in applied linguistics, second language learning, second language acquisition, and language education, particularly those with an interest in reading studies and research methods.