Introduction This chapter?s starting point lies in a previous paper dedicated to the study of the different interactions associated with the public education system in a Mexican indigenous community (Valdovinos 2014). In this earlier publication, I stated that, like any other public policy, literacy processes could not be fully understood by taking into account only their political dimensions (a ?top-down? perspective - cf. Lai, this volume) or else only their community-based point of view (a ?bottom-up? perspective). What I call ?mediating actors? - local institutions and the social actors related to them - must also be considered, since they are the participants directly involved in the actual adoption and institutionalization of policies. This chapter presents a case study in which mediating actors occupy a central position in the materialization of a particular linguistic policy - namely the adoption of an orthographic system for the Chwíse?etaana Náayeri (Cora Mariteco), an indigenous language spoken by approximately five thousand people in the state of Nayarit, in north-western Mexico. In 2012, organizing a workshop on orthography in the Náayeri community of Jesús María, I realized that this event represented an ideal opportunity for the study of the social dynamics of orthography development. Different questions arose from that experience and now serve as guidelines for the current discussion. These questions include: why were all previous attempts at creating an orthographic system for the benefit of the Mariteco set aside if the people of the community seemed so eager in such an endeavour? To what extent did the people of the community participate in previous attempts to develop an orthography? Was the lack of representation of the community in those former projects related to the rejection of the resulting orthographic systems? Was the nature of the linguistic analysis considered more important than any social involvement? Can the community truly play an active role in the development of an orthographic system? (For further consideration of these points, cf. Sackett, and Shah and Brenzinger, this volume.) My experience in organizing this workshop has led me to consider orthography development as a social process that must be conceived in its diachronic dynamism. The development of an orthography should not be reduced to a linguistic analysis that is imposed by an external group. © Cambridge University Press 2017.