Collaborative design of a reform-oriented mathematics curriculum: contradictions and boundaries across teaching, research, and policy Despina Potari 1 & Giorgos Psycharis 1 & Charalampos Sakonidis 2 & Theodossios Zachariades 1 # Springer Nature B.V. 2018 Abstract The reported study is situated within the process of developing a reform-oriented national mathematics curriculum for compulsory education in Greece by a design team that involved teachers, academic researchers, and policy-makers. From an activity theory perspective, we identify the activity systems of mathematics teaching, research in mathematics education, and educational policy interacting in the design process. We focus on the contradictions between the three activity systems and how these were dealt with. We based our analysis on email exchanges during the curriculum design, field notes from whole-team sessions, and interviews with key persons. Our results highlight that the emerging contradictions primarily concerned the teaching and research activity systems. Members of the team who acted as brokers between the different activity systems and facilitated their interaction played an important role in overcoming the contradictions. Keywords Mathematics curriculum design . Activity system . Boundary crossing . Boundary objects . Educational policy . Mathematics education research . Mathematics teaching 1 Introduction Educational innovations in centralised educational systems are usually introduced in a top- down way. However, the success of the innovation in large-scale contexts depends on how well it is integrated into the existing teaching reality. In mathematics education, a few studies have attempted to shed light on this complex process. For example, Krainer and Zehetmeier (2013) reported on their theoretical perspective of a large scale and long-term innovation Educational Studies in Mathematics https://doi.org/10.1007/s10649-018-9834-3 * Giorgos Psycharis gpsych@math.uoa.gr 1 National and Kapodistrian University of Athens, Athens, Greece 2 Democritus University of Thrace, Xanthi, Greece