This book is a collection of theoretical and empirical studies based on principled data collection methods, data analysis and interpretation.  It aspires to shed light on the diversity and interdisciplinarity of applied linguistics as contributors work with the data and perspectives that come from different fields such as psychology, sociology, education, language teaching, public policy, information technology and other areas of study. The contributors, applied linguists, implement a systematic language analysis based on the theories and multiple approaches that come from different fields in order to solve language-related problems. Therefore, this edited volume may be of great interest and importance for researchers, students, policy-makers and educators interested in applied linguistics research and implementation.