The democratization of schooling and greater access to higher education, together with the implementation of language requirements in colleges and universities across the United States, has led to a higher degree of diversity in language classrooms. One usually thinks of gender, ethnic, racial, or social diversity, but individual differences, including learning disabilities and special needs, also contribute to diversity and have an impact on assessment, placement, and curriculum. In their role as administrators and teacher educators, Language Program Directors (LPDs) seek to integrate current practices and research in applied linguistics into program design and administration, including assessment. To make individual differences a theoretically grounded integral component of their decision-making processes, LPDs need resources that provide cutting-edge primary and secondary research on the conceptualization, measurement, and consequences of individual differences on language development in the classroom.This volume provides LPDs with the means to transmit information to their instructors in effective ways so that the instructors develop a sophisticated understanding of individual differences, including learning disabilities, special needs, and strategies for dealing with diverse student populations. In addition, this volume creates a forum for reflections about and solutions to challenges related to diversity as it relates to individual differences.