There is an international trend in mathematics education of antiauthoritarianism, emphasising cooperative learning and students' autonomous search for knowledge. In Sweden, this is framed by "students' independent work", characterised by only limited amounts of teacher-student and student-student interaction and communication and a low level of teacher responsibility for knowledge generation. Research investigating occurrence and effects of different dimensions of instructional responsibility and authority in classroom practise, however, often takes the very presence of instructional responsibility for granted. In this paper, an alternative model for description and analysis of instructional practice is proposed, which challenges the potential of the traditional division into teacher- versus student-centred modes of instruction. Theoretical starting points for conceptualising and defining mathematics classroom practices focus on instructional responsibility both for knowledge generation and for how this responsibility would be expressed in instructional practice. It was also investigated how this model corresponds with data from TIMSS 2003. The empirical results supported the possibility of adopting this alternative perspective in modes of instruction. (Contains 2 tables, 2 figures and 1 footnote.)