Oral development in an additional language is surrounded by several obstacles (e.g. pronunciation, interactional, social, linguistic aspects), which may become thorny issues for teachers and learners of English (GOH & BURNS, 2012). In this book based on PhD thesis, I worked by means of a collaborative project concerning oral development in English (named My city - My World), which involved the use of additional technologies and digital resources in joint action with a schoolteacher in a Brazilian public school. In light of the principles of collaborative action research (BURNS, 2015), I aimed to detail and to assist in the oral development of students in English. The project activities were made up jointly with the schoolteacher and crafted in light of the epistemological axioms of the sociocultural theory (VYGOTSKY, 2001; JOHNSON, 2009). As results show, there is an effective collaboration between the teacher, the researcher and the students. Oral development was considerably possible due to the harmonious collaboration between the research participants and their engagement to learn and teach the English language collaboratively through the use of additional digital technologies.