This research study focuses on how teachers experience, negotiate and resolve tensions through the collaboration with other teachers and members of staff and the factors which may influence, support or undermine their role as inclusive teachers. For the purposes of this study, we drew upon Cultural Historical Activity Theory framework to examine the interconnectedness of the factors that may influence teachers' collaborative activities. We used Cyprus as our case study to explore the collective activity of collaboration (or lack of) between teachers and other members of staff in the school system. Research data revealed that teachers are increasingly aware of the value the collaboration with other teachers as a means to achieve inclusion more successfully. However, a number of factors including professional factors and contextual factors such as increased workload, lack of additional personnel in classrooms, curriculum demands and home-school relationship were found to create tensions in the activity of collaboration and consequently to affect the implementation of inclusion in the school system.