This longitudinal study investigates the impact of interaction with NSs on the development of oral communication skills and L2 confidence when students had an opportunity to use Japanese regularly outside the classroom with NSs in the community: Community Involvement (CI) project. In this study, students had a social interaction with Japanese NS living in Brisbane and the Gold Coast area. The subjects completed a questionnaire on perceived competence and anxiety measures and took listening and speaking tests before and after the ten-hour interaction. Written journals, which were collected after each meeting, were also analysed to examine the effect of interaction and account for the linguistic, cognitive, and affective changes which took place over the duration of the study. The results show that the subjects improve not only communication skills, but also significant changes in their confidence to communicate. The finding indicates that strong positive relationship between linguistic and psychological development during the project. This paper also presents a syllabus used for the project and the result of surveys collected from NSs.