Collaborative work in education is considered a strategy to respond to diversity in the classroom, consisting of the formation of work teams made up of different professionals. One of the modalities in which this strategy can be implemented is co-teaching. This research explores the conceptions and beliefs of pre-service mathematics teachers about co-teaching with a special education teacher. Design contemplates semi-structured interviews with 5 students in each cohort from a public university of Santiago de Chile, which were analyzed by means of a content analysis. The main results indicate: a) there is little consistency and coherence in the role of the teacher since participants generally refer to symmetrical collaborative work, but at the same time they agree that the role of the special educator is only to help; b) the type of co-teaching that most prevail in participant’s responses is "one teaches, one helps"; and c) future teachers conceptualize students` role under an integration paradigm and not an inclusion. We conclude that there are tensions in the thinking of future teachers regarding the implications of co-teaching work

Teaching strategies; Teacher' role; Student' role; Beliefs; Conceptions