This book is the compilation of eight research studies conducted by the students from the Master's in Education with Emphasis on English Didactics at the School of Education in Universidad Externado de Colombia, and one study carried out by the professors from the same Emphasis. It illustrates the students' research process focused on various English didactíc issues relevant to the EFL community of teachers. This issues comprise several themes such as materíals development for teachers' professional growth, undergraduate students' critical thinkíng skílls revealed through ín-dass debates on controversial íssues ín an EFL dassroorn, the enhancement of wrítíng through cooperative learning, the improvement of oral fluency through vocabulary learníng actívíties based on collocations, materials development for learning English for specific purposes, development of task-based vocabulary to enhance reading comprehension, the process approach to develop argumentative skills, meaningful photographs to engage students in oral activities, and fostering reading strategies through the use of authentic materials. This book divided into nine chapters. Each chapter explains the corresponding research process undergone by the students. It describes their theoretical considerations, instructional and research designs, data analysis and findings, and condusions in relation to their concern.